SPATIAL RENDERING OF REVERBERATION Field The present application relates to apparatus and methods for generating and employment of spatial rendering of reverberation, but not exclusively for spatial rendering of reverberation in augmented reality and/or virtual reality apparatus. Background Reverberation refers to the persistence of sound in a space after the actual sound source has stopped. Different spaces are characterized by different reverberation characteristics. For conveying spatial impression of an environment, reproducing reverberation perceptually accurately is important. Room acoustics are often modelled with individually synthesized early reflection portion and a statistical model for the diffuse late reverberation. Figure 1 depicts an example of a synthesized room impulse response showing amplitude 101 over time 103 where the direct sound 105 is followed by discrete early reflections 107 which have a direction of arrival (DOA) and diffuse late reverberation 109 which can also have a direction of arrival or be synthesized without any specific direction of arrival. One method of reproducing reverberation is to utilize a set of N loudspeakers (or virtual loudspeakers reproduced binaurally using a set of head-related transfer functions (HRTF)). The loudspeakers are positioned around the listener somewhat evenly. Mutually incoherent reverberant signals are reproduced from these loudspeakers, producing a perception of surrounding diffuse reverberation. The positioning and the number of the loudspeakers suitable for producing the diffuse perception has been studied. Examples of which are K. Hiyama, S. Komiyama, and K. Hamasaki, The Minimum Number of Loudspeakers and Its Arrangement for Reproducing the Spatial Impression of Diffuse Sound Field, AES 113 ^th Convention, 2002 and C. Kirch, J Poppitz, T. Wendt, S. van der Par, and S. Ewert, Spatial Resolution of Late Reverberation in Virtual Acoustic Environments. Submitted to Trends in Hearing (currently available at https://journals.sagepub.com/doi/full/10.1177/23312165211054 924), 2021. It has been found that somewhere around 6 – 12 loudspeakers are required, depending on the positioning of the loudspeakers. The reverberation produced by the different loudspeakers has to be mutually incoherent. In a simple case the reverberations can be produced using the different channels of the same reverberator, where the output channels are uncorrelated but otherwise share the same acoustic characteristics such as RT60 time and level (specifically, the diffuse-to-direct or diffuse-to-source ratio or reverberant-to-direct ratio). Such uncorrelated outputs sharing the same acoustic characteristics can be obtained, for example, from the output taps of a Feedback-Delay-Network (FDN) reverberator with suitable tuning of the delay line lengths, or from a reverberator based on using decaying uncorrelated noise sequences by using a different uncorrelated noise sequence for different channels. In this case, the different reverberant signals effectively have the same features, and the reverberation is typically perceived to be similar to all directions. In some other cases, the reverberation to different loudspeakers can be tuned based on the acoustic environment. For example, in some cases it is desirable to adjust the spatial characteristics of reverberation depending on the direction from which that portion of the diffuse late reverberation originates from. An example is using a shorter RT60 time for reverberation signals originating from the direction of a highly absorbing wall versus using a longer RT60 time for reverberation signals originating from the directions corresponding to acoustically more reflecting materials. In this case, the reverberation is different to different directions. Summary There is provided according to a first aspect a method for generating reverberant audio signals, the apparatus comprising: obtaining at least one audio signal; obtaining at least one spatial room impulse response; determining at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configuring at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generating at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. Determining at least one parameter based on the at least one spatial room impulse response may comprise determining a common decay rate parameter, wherein configuring the at least one reverberator based on the determined at least one parameter may comprise determining a common decay rate for at least one delay line attenuation filter of the at least one reverberator based on the common decay rate parameter and at least one dimension of at least one acoustic environment. Determining the common decay rate parameter may comprise determining the common decay rate parameter based on at least partially on an omnidirectional component of the at least one spatial room impulse response. Determining the common decay rate parameter may comprise: determining an energy decay curve from an omnidirectional component of the at least one spatial room impulse response; determining noise powers from the at least one spatial room impulse response; determining a denoised energy decay curve based on the determined energy decay curve and the noise powers; and determining the common decay rate parameter from the denoised energy decay curve. Determining the at least one parameter based on the at least one spatial room impulse response may comprise further determining at least one of: a pre- delay time based on the at least one spatial room impulse response; and an initial gain parameter based on the denoised energy decay curve at the pre-delay time. Determining a pre-delay time based on the at least one spatial room impulse response may comprise: determining a diffuseness of the at least one spatial room impulse response; averaging the diffuseness over frequencies of the at least one spatial room impulse response; and determining a time where the average of the diffuseness exceeds a determined threshold value, wherein the time is the pre- delay time. Determining the at least one parameter based on the at least one spatial room impulse response may comprise: determining a direct sound peak within the at least one spatial room impulse response; applying a windowing about the direct sound peak to determine an omnidirectional energy of the at least one spatial room impulse response and an energy of a direct sound impulse; determining a reverberant to direct ratio based on the omnidirectional energy of the at least one spatial room impulse response and an energy of a direct sound impulse. Configuring the at least one reverberator based on the determined at least one parameter may comprise: determining at least one beamformed impulse response for spatial directions associated with output channel directions of the at least one reverberator based on the at least one spatial room impulse response; determining a parameter for the at least one spatial direction based on the at least one beamformed impulse response; and determining at least one output channel gain coefficient of the at least one reverberator based on the at least one parameter. Obtaining at least one spatial room impulse response, may comprise obtaining an ambisonic impulse response measured in the at least one acoustic environment. Determining at least one beamformed impulse response for spatial directions associated with output channel directions of the at least one reverberator based on the at least one spatial room impulse response may comprise determining beamformed impulse responses based on an application of spherical harmonics in at least one determined loudspeaker direction applied to the at least one spatial room impulse response. Determining the at least one parameter for the at least one spatial direction based on the at least one beamformed impulse response may comprise: determining an energy decay curve from the at least one beamformed impulse response; determining noise powers from the at least one beamformed impulse response; determining a denoised energy decay curve based on the determined energy decay curve and the noise powers; and determining the directional decay parameter from the denoised energy decay curve. Determining at least one parameter based on the at least one spatial room impulse response may comprise: obtaining a further pre-delay time; and determining a further initial gain parameter based on the denoised energy decay curve at the further pre-delay time. Determining at least one parameter based on the at least one spatial room impulse response may comprise determining at least one directional gain based on a normalized further initial gain parameter. The further pre-delay time may be the pre-delay time. The at least one audio signal may be associated with at least one acoustic environment, and wherein the at least one spatial room impulse response may be defined by the at least one acoustic environment. The at least one parameter may comprise at least one directional decay parameter, the at least one directional decay parameter being for at least one spatial direction within the at least one acoustic environment. According to a second aspect there is provided an apparatus for generating reverberant audio signals, the apparatus comprising means configured to: obtain at least one audio signal; obtain at least one spatial room impulse response; determine at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configure at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generate at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. The means configured to determine at least one parameter based on the at least one spatial room impulse response may be configured to determine a common decay rate parameter, wherein the means configured to configure the at least one reverberator based on the determined at least one parameter may be configured to determine a common decay rate for at least one delay line attenuation filter of the at least one reverberator based on the common decay rate parameter and at least one dimension of at least one acoustic environment. The means configured to determine the common decay rate parameter may be configured to determine the common decay rate parameter based on at least partially on an omnidirectional component of the at least one spatial room impulse response. The means configured to determine the common decay rate parameter may be configured to: determine an energy decay curve from an omnidirectional component of the at least one spatial room impulse response; determine noise powers from the at least one spatial room impulse response; determine a denoised energy decay curve based on the determined energy decay curve and the noise powers; and determine the common decay rate parameter from the denoised energy decay curve. The means configured to determine the at least one parameter based on the at least one spatial room impulse response may be configured to further determine at least one of: a pre-delay time based on the at least one spatial room impulse response; and an initial gain parameter based on the denoised energy decay curve at the pre-delay time. The means configured to determine a pre-delay time based on the at least one spatial room impulse response may be configured to: determine a diffuseness of the at least one spatial room impulse response; average the diffuseness over frequencies of the at least one spatial room impulse response; and determine a time where the average of the diffuseness exceeds a determined threshold value, wherein the time is the pre-delay time. The means configured to determine the at least one parameter based on the at least one spatial room impulse response may be configured to: determine a direct sound peak within the at least one spatial room impulse response; apply a windowing about the direct sound peak to determine an omnidirectional energy of the at least one spatial room impulse response and an energy of a direct sound impulse; and determine a reverberant to direct ratio based on the omnidirectional energy of the at least one spatial room impulse response and an energy of a direct sound impulse. The means configured to configure the at least one reverberator based on the determined at least one parameter may be configured to: determine at least one beamformed impulse response for spatial directions associated with output channel directions of the at least one reverberator based on the at least one spatial room impulse response; determine a parameter for the at least one spatial direction based on the at least one beamformed impulse response; and determine at least one output channel gain coefficient of the at least one reverberator based on the at least one parameter. The means configured to obtain at least one spatial room impulse response, may be configured to obtain an ambisonic impulse response measured in the at least one acoustic environment. The means configured to determine at least one beamformed impulse response for spatial directions associated with output channel directions of the at least one reverberator based on the at least one spatial room impulse response may be configured to determine beamformed impulse responses based on an application of spherical harmonics in at least one determined loudspeaker direction applied to the at least one spatial room impulse response. The means configured to determine the at least one parameter for the at least one spatial direction based on the at least one beamformed impulse response may be configured to: determine an energy decay curve from the at least one beamformed impulse response; determine noise powers from the at least one beamformed impulse response; determine a denoised energy decay curve based on the determined energy decay curve and the noise powers; and determine the directional decay parameter from the denoised energy decay curve. The means configured to determine at least one parameter based on the at least one spatial room impulse response may be configured to: obtain a further pre- delay time; and determine a further initial gain parameter based on the denoised energy decay curve at the further pre-delay time. The means configured to determine at least one parameter based on the at least one spatial room impulse response may be configured to determine at least one directional gain based on a normalized further initial gain parameter. The further pre-delay time may be the pre-delay time. The at least one audio signal may be associated with at least one acoustic environment, and wherein the at least one spatial room impulse response may be defined by the at least one acoustic environment. The at least one parameter may comprise at least one directional decay parameter, the at least one directional decay parameter being for at least one spatial direction within the at least one acoustic environment. According to a third aspect there is provided an apparatus for generating reverberant audio signals, the apparatus comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the system at least to perform: obtaining at least one audio signal; obtaining at least one spatial room impulse response; determining at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configuring at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generating at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. The apparatus caused to determine at least one parameter based on the at least one spatial room impulse response may be further caused to perform determining a common decay rate parameter, wherein apparatus caused to configure the at least one reverberator based on the determined at least one parameter is caused to perform determining a common decay rate for at least one delay line attenuation filter of the at least one reverberator based on the common decay rate parameter and at least one dimension of at least one acoustic environment. The apparatus caused to determine the common decay rate parameter may be further caused to perform determining the common decay rate parameter based on at least partially on an omnidirectional component of the at least one spatial room impulse response. The apparatus caused to determine the common decay rate parameter may be further caused to perform: determining an energy decay curve from an omnidirectional component of the at least one spatial room impulse response; determining noise powers from the at least one spatial room impulse response; determining a denoised energy decay curve based on the determined energy decay curve and the noise powers; and determining the common decay rate parameter from the denoised energy decay curve. The apparatus caused to determine the at least one parameter based on the at least one spatial room impulse response may be further caused to perform determining at least one of: a pre-delay time based on the at least one spatial room impulse response; and an initial gain parameter based on the denoised energy decay curve at the pre-delay time. The apparatus caused to determine a pre-delay time based on the at least one spatial room impulse response may be caused to perform: determining a diffuseness of the at least one spatial room impulse response; averaging the diffuseness over frequencies of the at least one spatial room impulse response; and determining a time where the average of the diffuseness exceeds a determined threshold value, wherein the time is the pre-delay time. The apparatus caused to determine the at least one parameter based on the at least one spatial room impulse response may be caused to further perform: determining a direct sound peak within the at least one spatial room impulse response; applying a windowing about the direct sound peak to determine an omnidirectional energy of the at least one spatial room impulse response and an energy of a direct sound impulse; determining a reverberant to direct ratio based on the omnidirectional energy of the at least one spatial room impulse response and an energy of a direct sound impulse. The apparatus caused to configure the at least one reverberator based on the determined at least one parameter may be caused to perform: determining at least one beamformed impulse response for spatial directions associated with output channel directions of the at least one reverberator based on the at least one spatial room impulse response; determining a parameter for the at least one spatial direction based on the at least one beamformed impulse response; and determining at least one output channel gain coefficient of the at least one reverberator based on the at least one parameter. The apparatus caused to obtain at least one spatial room impulse response, may be further caused to perform obtaining an ambisonic impulse response measured in the at least one acoustic environment. The apparatus caused to determine at least one beamformed impulse response for spatial directions associated with output channel directions of the at least one reverberator based on the at least one spatial room impulse response may be further caused to perform determining beamformed impulse responses based on an application of spherical harmonics in at least one determined loudspeaker direction applied to the at least one spatial room impulse response. The apparatus caused to determine the at least one parameter for the at least one spatial direction based on the at least one beamformed impulse response may be caused to perform: determining an energy decay curve from the at least one beamformed impulse response; determining noise powers from the at least one beamformed impulse response; determining a denoised energy decay curve based on the determined energy decay curve and the noise powers; and determining the directional decay parameter from the denoised energy decay curve. The apparatus caused to determine at least one parameter based on the at least one spatial room impulse response may be further caused to perform: obtaining a further pre-delay time; and determining a further initial gain parameter based on the denoised energy decay curve at the further pre-delay time. The apparatus caused to determine at least one parameter based on the at least one spatial room impulse response may be caused to perform determining at least one directional gain based on a normalized further initial gain parameter. The further pre-delay time may be the pre-delay time. The at least one audio signal may be associated with at least one acoustic environment, and wherein the at least one spatial room impulse response may be defined by the at least one acoustic environment. The at least one parameter may comprise at least one directional decay parameter, the at least one directional decay parameter being for at least one spatial direction within the at least one acoustic environment. According to a fourth aspect there is provided an apparatus for generating reverberant audio signals, the apparatus comprising: obtaining circuitry configured to obtain at least one audio signal; obtaining circuitry configured to obtain at least one spatial room impulse response; determining circuitry configured to determine at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configuring circuitry configured to configure at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generating circuitry configured to generate at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. According to a fifth aspect there is provided a computer program comprising instructions [or a computer readable medium comprising instructions] for causing an apparatus, for generating reverberant audio signals, the apparatus caused to perform at least the following: obtaining at least one audio signal; obtaining at least one spatial room impulse response; determining at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configuring at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generating at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. According to a sixth aspect there is provided a non-transitory computer readable medium comprising program instructions for causing an apparatus, for generating reverberant audio signals, to perform at least the following: obtaining at least one audio signal; obtaining at least one spatial room impulse response; determining at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configuring at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generating at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. According to a seventh aspect there is provided an apparatus, for generating reverberant audio signals, comprising: means for obtaining at least one reverberation at least one audio signal; means for obtaining at least one spatial room impulse response; means for determining at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; means for configuring at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and means for generating at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. According to an eighth aspect there is provided a computer readable medium comprising instructions for causing an apparatus, for generating reverberant audio signals, to perform at least the following: obtaining at least one audio signal; obtaining at least one spatial room impulse response; determining at least one parameter based on the at least one spatial room impulse response, the at least one parameter being for at least one spatial direction; configuring at least one reverberator based on the determined at least one parameter such that the at least one reverberator is configured to output audio in the at least one spatial direction; and generating at least one reverberant audio signal based on the configured at least one reverberator and the at least one audio signal. An apparatus comprising means for performing the actions of the method as described above. An apparatus configured to perform the actions of the method as described above. A computer program comprising instructions for causing a computer to perform the method as described above. A computer program product stored on a medium may cause an apparatus to perform the method as described herein. An electronic device may comprise apparatus as described herein. A chipset may comprise apparatus as described herein. Embodiments of the present application aim to address problems associated with the state of the art. Summary of the Figures For a better understanding of the present application, reference will now be made by way of example to the accompanying drawings in which: Figure 1 shows a model of room acoustics and the room impulse response; Figure 2 shows schematically an example apparatus within which some embodiments may be implemented; Figure 3 shows a flow diagram of the operation of the example apparatus as shown in Figure 2; Figure 4 shows schematically an example reverberator parameter determiner as shown in Figure 2 according to some embodiments; Figure 5 shows a flow diagram of the operation of the example reverberator parameter determiner as shown in Figure 4 according to some embodiments; Figure 6 shows an example determination of the pre-delay based on when a running estimate of diffuseness exceeds a predetermined threshold value or level; Figure 7 shows an example of analysing RT60 and initial gain from an energy decay function of the omni-directional room impulse response; Figure 8 shows schematically an example directional gain determiner as shown in Figure 2 according to some embodiments; Figure 9 shows a flow diagram of the operation of the example directional gain determiner as shown in Figure 8; Figure 10 shows an example of modelling spatially non-uniform reverberation with uniform decay with different gain level; Figure 11 shows schematically an example reverberator as shown in Figure 2 according to some embodiments; Figure 12 shows a flow diagram of the operation of the example reverberator as shown in Figure 11; Figure 13 shows schematically an example FDN reverberator as shown in Figure 11 according to some embodiments; Figure 14 shows a flow diagram of the operation of the example reverberator controller shown in Figure 12; Figure 15 shows schematically an example binaural renderer as shown in Figure 2 according to some embodiments; Figure 16 shows a flow diagram of the operation of the example binaural renderer as shown in Figure 15; Figure 17 shows schematically an example apparatus with transmission and/or storage within which some embodiments can be implemented; and Figure 18 shows an example device suitable for implementing the apparatus shown in previous figures. Embodiments of the Application The following describes in further detail suitable apparatus and possible mechanisms for parameterizing and rendering audio scenes with reverberation. Thus for example the suitable apparatus and methods can be part of a spatial audio rendering (also known as spatial rendering). As discussed above reverberation can be rendered using, e.g., a Feedback- Delay-Network (FDN) reverberator with a suitable tuning of delay line lengths. An FDN allows to control the reverberation times (RT60) and the energies of different frequency bands individually. Thus, it can be used to render the reverberation based on the characteristics of the room or modelled space. The reverberation times and the energies of the different frequencies are affected by the frequency- dependent absorption characteristics of the room. In the case of a room with fully diffuse late reverberation, the reverberation characteristics are identical in any direction. In that case, the same acoustic characteristics can be used to adjust the different channels of, e.g., an FDN reverberator. Known methods using impulse responses can be used to derive such acoustical characteristics, e.g., using an omnidirectional impulse response. However, in real life, the late reverberation in rooms is rarely fully diffuse. Instead, the late reverberation is different to different directions. However setting the late reverberation to be the same in all directions can produce ‘unrealistic’ effects, and thus degrade the quality of the rendering. Especially in the case of AR rendering, there is a desire to produce a realistic rendering of the late reverberation in order to implement a seamless perception of the real sound sources in the room and the augmented audio sources rendered to the listener. If the late reverberation in the room is not equal to all directions, there will be a discrepancy between the perception of the real sources (having non-equal directional characteristics in the late reverberation) and the augmented sources (having equal directional characteristics in all directions). Another proposed option is to determine the absorption coefficients for all surfaces in the room and to determine the direction-dependent acoustical characteristics using these coefficients. This is a viable option for VR rendering, where the content creator may manually set the needed information and/or offline encoder processing can be used to perform a computationally intensive acoustic simulation to produce spatial room impulse responses using the absorption coefficients. However, this is not a suitable option for systems which acquire the information automatically. For example in AR rendering, the required information is obtained automatically using impulse responses in order to allow a user device to capture the acoustical characteristics of the room where the device is, and to bring augmented audio sources realistically to the space. Yet another possible option is to analyze reverberation characteristics which are different in different directions of a room. However, such methods can lack the possibility to configure a digital reverberator based on the analysis or ways to render the reverberation for a listener. Also, some known methods present ways to render non-uniform reverberation characteristics to different spatial directions using a digital reverberator but such methods are computationally intensive. The aim thus is to obtain automatically (e.g., using impulse responses) directional reverberation characteristics and use those computationally efficiently to render reverberation that match the (directional) reverberation characteristics of a (real) room. This avoids the need to either lose the directional characteristics (which makes the rendering unrealistic) or require manual tuning of reverberator characteristics (which prevents usages in systems requiring automatic operation, such as, AR rendering). The concept as discussed in the embodiments herein in further detail is one which relates to reproduction of (late) reverberation, where (apparatus configured to implement) a method is proposed that enables automatic capture of (directional) reverberation characteristics using impulse response(s) of a (physical) room and rendering of reverberation using the captured characteristics so that the characteristics (including the directional characteristics) of the rendered reverberation are related to the reverberation characteristics of the (physical) room. In some embodiments this can be achieved by obtaining a spatial room impulse response (SRIR), determining a directional decay parameter for at least one spatial direction using the SRIR, based on the determined at least one directional decay parameter, adjusting a reverberator in order to control the output in the corresponding direction(s), and furthermore rendering a reverberated signal using the reverberator and at least one input signal. In some embodiments, a Feedback-Delay-Network (FDN) reverberator with N output channels is used. The output channels are related to N spatial directions surrounding the listener. The outputs of the reverberator can be reproduced with (virtual or real) loudspeakers in the corresponding directions. N can in an example be 15. Other suitable values for N can be for example 7, 8, 16, 31, 32, 63, 64. In these embodiments, the input SRIR may be an Ambisonic impulse response measured in a room (an acoustic space). First, using the omnidirectional component of the SRIR, a common decay rate parameter is estimated. Then, the common decay rate for the delay line attenuation filters (of all channels) of the FDN are adjusted using the common decay parameter and at least one dimension parameter associated with the room. Next, beamformed impulse responses are determined for spatial directions (corresponding to the output channel directions of the FDN) using the SRIR. Using the beamformed impulse responses, a directional decay parameter is determined for spatial directions. Then, the output channel gain coefficients of the FDN reverberator are adjusted by the corresponding directional decay parameters. Finally, the input audio signal can be reverberated using the adjusted FDN reverberator. As an output, there are 15 (in this example) mutually (almost) incoherent reverberant signals. The output signals can be reproduced using loudspeakers (or alternatively virtual loudspeakers that are convolved with HRTFs) that are positioned in the directions corresponding to the spatial directions used above and controlled with the channel gain coefficients. The resulting reverberation is perceived to have reverberation characteristics matching the room where the SRIR was captured. Also the directional characteristics of the reverberation are matching the room since the decay characteristics of the output channels are controlled with the output channel gain coefficients which were adjusted based on the directional decay parameters. Moreover, the directional reverberation processing can be performed with low computational complexity, as the FDN reverberators are computationally efficient and rendering directional reverberation characteristics only requires applying gains on the output channels. It is noted that the method does not explicitly try to adjust the directional decay of the reverberation output to match the analyzed directional decay. Instead, the level of directional decay is adjusted based on the analyzed directional decay parameters. The benefit of this is reduced computational complexity as different spatial directions do not need to have different reverberators with different decays. Still, the method achieves the goal of producing the desired perceptual goal of having an uneven power distribution of the late energy towards different spatial directions as the level of the reverberation is different to different spatial directions even if the decay (RT60) characteristics are shared by different spatial directions. The proposed embodiments are particularly useful for augmented reality (AR) audio rendering, as it can determine the needed information automatically using only the impulse response(s) and the room dimensions, without a need for manual tuning of the reverberation parameters. Moreover, the embodiments as discussed herein can be modified without significant effort to be used in other use cases, such as virtual reality (VR) audio rendering, where the embodiments can provide the same advantage of automatic determination of the needed parameters (such that virtual room reverberation characteristics are provided/modeled based on a captured or simulated SRIR input to the system). Figure 2 shows a schematic view of an example apparatus suitable for implementing some embodiments. This example apparatus is configured to receive as inputs, audio signal 200, spatial room impulse response (SRIR) 202, loudspeaker setup 204, and room dimensions 206. The apparatus is configured to render reverberant binaural signals 214 as an output, containing late reverberation which is perceived equally as if the sound source were actually in the room where the spatial room impulse response 202 was measured. It should be noted that this apparatus is configured to show only late reverberation rendering and that direct sound and early reflections rendering would be considered separately and are not described in further detail. The spatial room impulse response 202 ℎ _^^^^ (^, ^) contains impulse responses having ^ channels measured in a room (where ^ is time in samples and ^ the impulse response channel). For example the impulse responses can be the channels of (first-order or higher-order) Ambisonic room impulse response (which can, for example, be obtained by measuring the impulse responses using a dedicated microphone, such as Eigenmike). In some embodiments the apparatus comprises a reverberation parameter determiner 201 which is configured to receive the spatial room impulse response 201 ℎ _^^^^ (^, ^). The reverberation parameter determiner is configured to determine suitable (non-directional) parameters 208 for configuring the reverberator 205. In some embodiments the reverberation parameters 208 can comprise the reverberation times ^ _^^ (^) in frequency bands (where ^ is the frequency band index), overall gain ^ _^ (^) in frequency bands, and the pre-delay ^. The reverberation parameters 208 can, for example, be determined using the omnidirectional component of the spatial room impulse response 202 ℎ _^^^^ (^, ^). In some embodiments the apparatus further comprises a directional gains determiner 203. The directional gains determiner 203 is configured to receive or obtain the spatial room impulse response 202 ℎ _^^^^ (^, ^) and also loudspeaker setup 204. The loudspeaker setup 204 is a surrounding loudspeaker setup that can be used for creating a perception of enveloping diffuse reverberation. As an example, the following setup can be used: Azimuth 90, -90, 114, -60, 85, -130, 49, -67, 154, -48, 19, -162, 151, -9, 180 degrees. Elevation ^ _^^ (^): 0, 0, 20, -6, -44, -21, 41, 52, -9, -55, -31, 21, 733, 20, 63 degrees. This setup is suitable when the number of output channels N equals 15. When the number of output channels is different then different setup can be used such that it sufficiently covers directions around a listener. The directions ^ _^^ (^), ^ _^^ (^) correspond to the output channels ^ of the reverberator 205. Using the spatial room impulse response 202 ℎ _^^^^ (^, ^), the directional gains determiner 203 is configured to determine a directional gain 210 for directions ^ _^^ (^), ^ _^^ (^) of the loudspeaker setup 204. The directional gains 210 can in some embodiments be determined based on directional decay parameters determined from the spatial room impulse response 202. In some embodiments the apparatus comprises a reverberator 205. The reverberator 205 is configured to receive the reverberation parameters 208 ^ _^^ (^), ^ _^ (^), ^ and the directional gains 210 ^ _^ (^) along with the audio signal 200 ^ _^^ (^). In some embodiments, the reverberator 205 may also receive the loudspeaker setup 204 and the room dimensions 206 that may be used to optimize the reverberation (however, this is optional). In other words the reverberator can be configured or adjusted based on the determined parameters. Where the description describes configuring the reverberator, this configuring can be viewed as a modification or adjustment of the reverberator. The reverberator 205 in some embodiments is implemented using a Feedback-Delay-Network (FDN) reverberator. In this example embodiment, the FDN reverberator has ^ = 15 output channels ^. (However any suitable number of channels can be employed). The resulting directional reverberant audio signals 212 ^ _^^^ (^, ^) are mutually incoherent, and have non-directional acoustical characteristics according to the reverberation parameters 208 and the directional acoustical characteristics according to the directional gains 210. In some embodiments the apparatus further comprises a binaural renderer 207. The binaural renderer 207 in some embodiments is configured to receive the directional reverberant audio signals 212 ^ _^^^ (^, ^) and also receive the loudspeaker setup 204. The binaural renderer 207 is configured to render the reverberated audio signals to generate reverberant binaural signals 214 ^ _^^^ (^, ^ _^^^ ) (where ^ _^^^ is the binaural channel), which can, for example, be reproduced using headphones or other suitable output apparatus. These reverberant binaural audio signals 214 are perceived as surrounding and enveloping and having the directional and the non- directional acoustical characteristics according to the room where the spatial room impulse response 202 ℎ _^^^^ (^, ^) was measured. With respect to Figure 3 is shown a flow diagram showing the operations of the example apparatus shown in Figure 2 according to some embodiments. The method can comprise as shown by 301 obtaining the audio signal, spatial room impulse response, loudspeaker setup (and optionally room dimensions). Then, the reverberation parameters are determined as shown by 303. The directional gains are then determined as shown by 305. Reverberation is applied to the audio signals based on the reverberation parameters, the directional gains and optionally also the room dimensions and loudspeaker setup as shown by 307. Then a binaural rendering of the reverberant binaural audio signals are generated from the directional reverberant audio signals as shown by 309. The reverberant binaural audio signals are then output as shown by 311. With respect to Figure 4 is further shown an example reverberation parameter determiner 201 in further detail according to some embodiments. The reverberation parameter determiner 201 is configured to receive the spatial room impulse response 202. In some embodiments the reverberation parameter determiner 201 comprises a short time Fourier transform (STFT) 201 which receives the SRIR and generates a time-frequency domain room response 402. The SRIR is thus transformed by a short time-frequency transform from ℎ _^^^^ (^, ^) to ℎ _^^^^ (^, ^, ^), where n and m are the frame and frequency bin indices, respectively. A range of bins is selected above the modal range of the room response and up to below the spatial aliasing limit of the microphone array, e.g., from 1kHz to 4~5kHz. Furthermore the reverberation parameter determiner 201 comprises direction of arrival (DOA) calculator 405 which is configured to receive the time- frequency domain room response 402 and generate direction of arrival values 406. In some embodiments a DOA analysis employed using B-format signals is that as described in Jukka Ahonen, Ville Pulkki, Diffuseness Estimation Using Temporal Variation of Intensity Vectors, IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, New Paltz, NY, USA, October 18-21, 2009, pp.337-340. However in some alternative embodiments, in particular ones using different microphone arrays, a different DOA analysis method such as the one described in Archontis Politis, Symeon Delikaris-Manias, Ville Pulkki, Direction-of-arrival and diffuseness estimation above spatial aliasing for symmetrical directional microphone arrays, 2015 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) can be used. The reverberation parameter determiner 201 comprises a diffuseness values calculator 409 configured to obtain the direction of arrival values 406 and output diffuseness values 410. The diffuseness value can be determined for time- frequency bins (n,m) up to below the spatial aliasing limit of the array based on the temporal fluctuation of the short-time narrowband direction-of-arrival vector determined by the DOA calculator 403. The diffuseness estimation may employ any suitable method such as described in the references noted above. Additionally the reverberation parameter determiner 201 comprises an across frequency averager 413 configured to average the diffuseness values 410 across frequencies and generate averaged diffuseness values 414. In the Frequency averager 413 the narrowband diffuseness values ψ(n,m) are then averaged across frequency to result in a broadband diffuseness value ψ _bb (n). The reverberation parameter determiner 201 furthermore comprises a level crossing determiner 417 configured to determine level crossings of the averaged diffuseness values and output these 418. The averaged diffuseness value remains low for the early part of the SRIR, and then rises as it transitions from the early to the late part. The level crossing determiner is configured to determine when the average value crosses a suitable threshold (e.g., 0.8). With respect to Figure 6 is shown a graph of the room impulse response 601, the averaged or broadband diffuseness value 603 and furthermore an example threshold 605 and the point 607 at which the threshold is crossed by the broadband diffuseness value 603. Furthermore the reverberation parameter determiner 201 comprises a predelay estimator 421 configured to estimate a predelay value 422 d based on the level crossing information 418. Thus the predelay d is effectively computed from the spatial RIR based on a running measure of diffuseness ψ=[0,1], which indicates how complex the spatial structure of the SRIR is across time, ranging from 0 for a single broadband reflection in isolation, to 1 for a structure that is the result of multiple incoherent echoes arriving from multiple directions, characteristic of late reverb conditions. The mixing time is determined by when that value crosses a suitable threshold (e.g., 0.8). Furthermore in some embodiments the reverberation parameter determiner 201 comprises a filterbank 403 configured to receive the SRIR and decompose the SRIR into a number of subbands determined by a desired parameterization. In an example the filterbank 403 is a suitable octave-band filterbank where the subset of octave center frequencies are at [125, 250, 500, 1000, 2000, 4000] Hz, and the SRIR is decomposed into six respective SRIRs 404 ℎ _^^^^ (^, ^, ^), where k is the subband index. The rest of the parameters are then computed independently in frequency bands, and for simplicity the following process is described for one of the subbands. The reverberation parameter determiner 201 comprises an energy decay curve (EDC) calculator 407. The EDC calculator 407 is configured to receive the SRIR subband and determine an EDC 408 output. In the following examples an omnidirectional representation of the RIR, (which could be the first channel of a B- format SRIR, ℎ _^^^^ (^, ^) = ℎ _^^^^ (^, ^, 1)), the energy decay curve ^^^(^, ^) for the certain subband, can be produced by backwards integrating ℎ _^^^^ ⁽ ^, ^ ⁾ : where N is the total length of the SRIR in samples. Also in some embodiments the reverberation parameter determiner 201 comprises a noise power calculator 411. Since the input is measured RIRs, there is most likely measurement noise in the response which can bias the estimation of those parameters. The noise can be from ambience or from the microphones themselves, and is assumed additive, stationary, and uncorrelated with the clean RIR, which results in the following signal model: ^^^ ⁽ ^, ^ ⁾ = ^^^ _^^^ ⁽ ^, ^ ⁾ + ^^^ _^^^^^ (^, ^) Since the noise is assumed stationary with power per sample ^ _^^^^^ (^), the modeled noise EDC is linear, given by while the EDC of the RIR is assumed to follow a weighted exponential decay form of the type with the decay rate given by Since RIR decays below the noise floor after some time, the noise EDC can be computed by some late segment in the measurement, e.g., for t>1 sec in normal rooms. The EDC of that segment can then be assumed to be dominated mainly by the noise term, and a line can be fit to extrapolate the noise EDC across the whole range of the RIR. Thus the noise power calculator 411 can be configured to estimate the noise power 412 based on a late segment in the measurement. This for example is shown in Figure 7 which shows a first graph 700 of an example RIR 702 and noise 704 and which shows the noise dominated region from which the noise power Pin can in this example be estimated 705. The reverberation parameter determiner 201 can further comprise a noise EDC calculator 415 which based on the noise power Pin 412 is configured to determine a noise EDC (fit line) 416. This for example is shown on the second graph 720 of Figure 7 by the line 708. Additionally the reverberation parameter determiner 201 comprises a denoised EDC calculator 419. The denoised EDC calculator 419 is configured to subtract the noise EDC (Figure 7 line 708) from the noisy EDC values (as shown in Figure 7 by line 721) to generate denoised EDC values 420 (as shown in Figure 7 by line 719). In other words denoised ^^^ _^^^ ⁽ ^, ^ ⁾ can then be estimated by subtracting the modeled noise ^^^ _^^^^^ (^, ^) from ^^^ ⁽ ^, ^ ⁾ calculated from the measured RIR ^^^ _^^^ ⁽ ^, ^ ⁾ = ^^^ ⁽ ^, ^ ⁾ − ^^^ _^^^^^ (^, ^) The reverberation parameter determiner 201 comprises a RT60 calculator 423. The RT60 calculator 423 can receive the denoised EDC values 420 ^^^ _^^^ ⁽ ^, ^ ⁾ and by expressing the EDC in decibels, where the exponential form converts to a linear form (such as shown in the third graph 730 of Figure 7 by line 733 EDC _db and compared to the noisy EDC in linear form as shown by line 735). A line then is fit 711 to the denoised EDC, starting from a time point that avoids the early part (which typically deviates from the exponential model of the later part), e.g., at -5dB to -10dB from the maximum of the EDC. The end point can be taken at -20dB or -30dB from the first point, and the corresponding time interval between the two is multiplied by 3 or by 2 respectively, to get scaled to RT60717. The RT60 value 424 can be output. Furthermore the reverberation parameter determiner 201 comprises a delay rate calculator 425 which knowing the RT60 value 424 can compute the decay rate a(k) given by The reverberation parameter determiner 201 can then comprise an initial gain calculator 427 configured to receive the decay rate 426 and predelay 422 to determine the initial gain ^ _^,^^ = 20^^^ _^^ (^ _^ ) by the denoised EDC value at the predelay d. This is shown for example in Figure 7 by gain value g0,db 753 at mixing time T_mix 751 on line 755. In some embodiments the reverberation parameter determiner 201 comprises an RDR calculator which alternatively, or in addition to the initial gain, is configured to determine an estimated reverberant to direct ratio (RDR) expressing the total energy of the late reverberation with respect to the energy of the direct sound. That can be estimated by the omnidirectional energy of the measured impulse response over the energy of the direct sound impulse after appropriate windowing. After detecting the direct sound peak, and windowing with a window of, e.g., 5 msec centered around it, the direct sound energy is ^ _^^^ ^^ _^^^ ^ _^^^ (^) = ^ _^ ^{^} _^^   ^ ^)|^ ^^^ _^^^ ^^ _^^^ where ^ _^^^ is the direct peak index and ^ _^^^  is the source-receiver distance, used to normalize the RDR to 1m reference source receiver distance. The late sound energy is the unnormalized EDC value at the mixing time: ^ _^^^^ ⁽ ^ ⁾ = ^^ ⁽ ^ ⁾ ^^^ _^^^ ⁽ ^, ^ ⁾ , where ^^ ⁽ ^ ⁾ is the directivity factor of the source if known, used in order to compensate the RDR to an omnidirectional reference case. In some embodiments where the source directivity is unknown then the value of can be set to 1, ^^ ⁽ ^ ⁾ = 1. Finally, the total broadband RDR is given by In some embodiments the RDR can be converted to diffuse-to-source- energy-ratio or other reverberation ratio parameter. The output of the reverberation parameter determiner 201 is the reverberation parameters 200, which can comprise the RT60s 451, the decay rates 453, predelay 455, initial gains 457 and RDR 459. With respect to Figure 5 is shown a flow diagram of the operations of the example reverberation parameter determiner 201 as shown in Figure 4. As shown by 501 the SRIR is obtained or otherwise received. The SRIR can then be Short-time-Fourier-transformed (STFT) as shown by 503. The DOA or intensity vector determination is employed as shown by 505. The diffuseness values are determined or calculated as shown by 507. The diffuseness values are averaged to generate broadband diffuseness values as shown by 509. Then a level crossing between the broadband diffuseness values and a determined threshold value is detected as shown by 511. Then based on the level crossing the pre-delay value is estimated as shown by 513. Furthermore in parallel with the STFT a filterbank can be applied to the SRIR to determine a number of sub-band SRIR values as shown by 502. An EDC can then be calculated for sub-bands as shown by 504. The noise powers associated with the sub-band can furthermore be determined as shown by 506. The denoised EDCs can then be determined or calculated as shown by 508. RT60s can then be calculated from the denoised EDCs as shown by 510. The decay rates can be determined or calculated from the estimated RT60s as shown by 512. Initial gains can then be determined from the decay rates and the predelay values as shown by 515 and furthermore optionally or alternatively the RDRs can be calculated as shown by 517. The reverberation parameters can then be output as shown by 519. With respect to Figure 8 is shown a schematic view of the directional gains determiner 203 as shown in Figure 2. The directional gains determiner is configured to analyze directional gains from beamformed SRIRs using the processing of reverberation parameter determiner 201. The directional gain determiner 203 is therefore configured to calculate the directional gains ^ _^ for the loudspeaker directions, based on a similar EDC analysis, as presented above, for the portion of reverb that is concentrated around that direction. In some embodiments the directional gains determiner 203 comprises a beamformer 801. The beamformer 801 is configured to receive the spatial room impulse response (SRIR) 202 and the loudspeaker directions 204, which computes beamformed impulse responses for the directions of the loudspeakers ^ in the loudspeaker directions 204. For example in some embodiments the operation is based on beamforming with Ambisonic signals, formulated as where ^ _^ are real spherical harmonics ordered with the ACN ambisonic ordering and ^ _^ are ambisonic order-dependent weights controlling the shape of the beamformer (e.g., cardioid, hypercardioid, or supercardioid patterns). After the beamformed SRIRs 802 have been obtained, they are forwarded to the reverberation parameter determiner 803. The directional gains determiner 203 furthermore comprises the reverberation parameter determiner 803 which receives the beamformed SRIRs 802. The reverberation parameter determiner 803 can in some embodiments operate in the same manner as presented above for the omnidirectional component (containing the same EDC calculation and denoising process), but the processing is applied for beamformed responses ℎ _^^^^ (^, ^, ^) instead of the omnidirectional response. The directional gains determiner 203 in some embodiments is configured to determine pre-delay or beamformed pre-delay values in a manner similar as described as above but with respect to the beamformed SRIRs. However in some embodiments the pre-delay value used is the pre-delay value determined using the SRIRs as discussed above. The reverberation parameter determiner 803 can thus be configured to generate parameters 804 such as ^^^ ^ ^ _^^ ⁽ ^, ^, ^ ⁾ and initial power values ^ _^,^^ . In some embodiments the reverberation parameter determiner 803 furthermore comprises an initial power values normalizer 805. The initial power values normalizer 805 is configured to receive the parameters as ^^^ _^^^ ⁽ ^, ^, ^ ⁾ and initial power values ^ ^ ^ _,^^ and normalize the values around their mean dB value such as: ^ _^,^^ and their linear versions ^ _^ = 10 ^{^^} are applied to the FDN outputs Using the directional gains 210 simplifies the reverberation modeling and rendering. Figure 10 depicts an example where the first graph 1001 of Figure 10 shows for example where spatially nonuniform reverberation is modelled with different decays to different directions as shown by the differing gradients and initial gains for the solid, dash and dot lines representing the different directions. The second graph 1003 shows a simplified modelling of spatially nonuniform reverberation with uniform decays to different directions as shown by the same gradients but different initial gain values for the solid, dash and dot lines representing the different directions. With respect to Figure 9 is shown a flow diagram showing the operations of the example directional gain determiner according to some embodiments. For example as shown by 901 is shown the operation of obtaining the SRIR and loudspeaker directions. Then there is the operation of beamforming the SRIR based on the loudspeaker directions as shown by 903. The determination of the reverberation parameters is shown by 905. Furthermore the initial power values are normalized as shown in 907. Then the direction gains are then output as shown by 909. With respect to Figure 11 is shown in further detail a schematic view of the reverberator 205 as shown in Figure 2. In some embodiments the reverberator comprises a reverberation controller 1101. The reverberator controller 1101 is configured to receive or otherwise obtain reverberation parameters, room dimensions and loudspeaker setup and initialize the, in this example, FDN reverberator 1103 using reverberator parameters 1102. Additionally the reverberator comprises a FDN reverberator 1103. The FDN reverberator 1103 is configured to receive the reverberator parameters and based on these control the reverberation applied to the audio signal 200 to generate directional reverberant audio signals 202. Figure 13 shows an example FDN reverberator 1103 in further detail and which can be used to produce D uncorrelated output audio signals. The example FDN reverberator is configured such that the reverberation parameters are processed to generate coefficients GEQ _d (GEQ ₁ , GEQ ₂ ,… GEQ _D ) of the attenuation filters 1361, feedback matrix 1357 coefficients A, lengths m _d (m ₁ , m2,… mD) for D delay lines 1359 and DDR energy ratio control filter 1353 coefficients GEQddr. The DDR energy ratio control filter can also be referred as RDR energy ratio control filter or reverberation ratio control filter or reverberation equalization or coloration filter. The purpose of such a filter is to adjust the level and spectrum according to the RDR or other reverberation ratio data. The example FDN reverberator thus shows a D-channel output, by providing the output from the FDN delay lines as a separate output. In some embodiments the attenuation filter GEQd 1361 is implemented as a graphic EQ filter using M biquad IIR band filters. With octave bands M=10, thus, the parameters of the graphic EQ comprise the feedforward and feedback coefficients for biquad IIR filters, the gains for biquad band filters, and the overall gain. The reverberator uses a network of delays 1359, feedback elements (shown as attenuation filters 1361, feedback matrix 1357 and combiners 1355 and output gain 1363) to generate a very dense impulse response for the late part. Input samples are input to the reverberator to produce the reverberation audio signal component which can then be output. The FDN reverberator comprises multiple recirculating delay lines. The unitary matrix A 1357 is used to control the recirculation in the network. Attenuation filters 1361 which may be implemented in some embodiments as graphic EQ filters implemented as cascades of second-order-section IIR filters can facilitate controlling the energy decay rate at different frequencies. The filters 1361 are designed such that they attenuate the desired amount in decibels at the pulse pass through the delay line and such that the desired RT60 time is obtained. With octave bands M=10, thus, the parameters of the graphic EQ comprise the feedforward b and feedback a coefficients for 10 biquad IIR filters, the gains for biquad band filters, and the overall gain. The number of delay lines D can be adjusted depending on quality requirements and the desired tradeoff between reverberation quality and computational complexity. In an embodiment, an efficient implementation with D=15 delay lines is used. This makes it possible to define the feedback matrix coefficients A as proposed by Rocchesso in Maximally Diffusive Yet Efficient Feedback Delay Networks for Artificial Reverberation, IEEE Signal Processing Letters, Vol.4. No.9, Sep 1997, in terms of a Galois sequence facilitating efficient implementation. For this reverberator the reverberator parameters contain the coefficients of the attenuation filter GEQd 1361, feedback matrix coefficients A 1357, and lengths md for D delay lines 1359. In addition, diffuse-to-direct ratio filter GEQDDR coefficients are included. In this invention, the attenuation filter GEQ _d is a graphic EQ filter using M biquad IIR band filters. With octave bands M=10, thus, the parameters of the graphic EQ comprise the feedforward and feedback coefficients for 10 biquad IIR filters, the gains for biquad band filters, and the overall gain. The parameters also contain the length ^^^^ of the predelay line ^ ^{^^^^^} 1301 and the output channel gains ^ _^ 1363. A flow diagram of the operation of the reverberator controller as shown in Figure 11 is further described herein. The reverberation parameters room dimensions loudspeaker setup and directional gains are first obtained as shown by 1400. Then based on the room dimensions the delay line lengths can be determined as shown by 1401. For example, a shoebox shaped room can be defined with dimensions xDim, yDim, zDim. If the room is not shaped as a shoebox (or cuboid) then a shoebox can be fit inside the room and the dimensions of the fitted shoebox can be utilized for obtaining the delay line lengths. Alternatively, the dimensions can be obtained as three longest dimensions in the non-shoebox shaped room, or other suitable method. Then based on the delay line lengths and RT60(k) the delay line attenuation filter gains are determined as shown by 1403. The attenuation filter coefficients in the delay lines are adjusted so that a desired amount in decibels of attenuation happens at the signal recirculation through the delay line so that the desired RT60 time is obtained. This is done in a frequency specific manner to ensure the appropriate rate of decay of signal energy at specified frequencies. For example with respect to a frequency k, the desired attenuation per signal sample is calculated as attenuationPerSample(k) = -60 / (samplingRate * rt60(k)). The attenuation in decibels for a delay line of length md is then attenuationDb(k) = md * attenuationPerSample(k). The attenuation filters are designed as cascade graphic equalizer filters as described in V. Välimäki and J. Liski, “Accurate cascade graphic equalizer,” IEEE Signal Process. Lett., vol.24, no.2, pp.176–180, Feb.2017 for the delay line. The design procedure outlined in the above reference takes as input a set of command gains at octave bands. There are also methods for a similar graphic EQ structure which can support third octave bands, increasing the number of biquad filters to 31 and providing better match for detailed target responses such as described in Third- Octave and Bark Graphic-Equalizer Design with Symmetric Band Filters, https://www.mdpi.com/2076-3417/10/4/1222/pdf. Other suitable filters such as polynomial IIR filters or FIR filters can be used in alternative embodiments. Furthermore based on the overall gain or reverberation ratio parameter the reverberation ratio control filter parameters can be obtained as shown by 1405. The filter is designed such that, when the filter is applied to the input data of the FDN reverberator, the output reverberation will have the desired energy ratio defined by the ^^^(^). The input to the design procedure are the RDR values ^^^ ⁽ ^ ⁾ obtained by the Reverberation parameter determiner. The GEQDDR matches the reverberator spectrum energy to the target spectrum energy. In order to do this, an estimate of the RDR of the reverberator output and the target RDR are obtained. The RDR of the reverberator output can be obtained by rendering a unit impulse through the reverberator using the first reverberator parameters and measuring the energy of the reverberator output and energy of the unit impulse and calculating the ratio of these energies. A unity impulse input where the first sample value is 1 and the length of the zero tail is long enough is created. In practice, the length of the zero tail is adjusted to equal max(RT60(k)) plus the ^ in samples. The monophonic output of the reverberator can be used in the adjustment of overall gain or energy so summed over the delay lines j to obtain the reverberator output ^ _^^^ ⁽ ^ ⁾ as a function of time t. A long FFT (of length NFFT) is calculated over ^ _^^^ (^) and its absolute value is obtained as FFA(kk) = abs(FFT(^ _^^^ ⁽ ^ ⁾ ) Here, kk are the FFT bin indices. We furthermore obtain the positive half spectral energy density as S(kk) = 1/NFFT * FFA(kk) ² where the energy from the negative frequency indices kk is added into the corresponding positive frequency indices kk. The energy of a unit impulse can be calculated or obtained analytically and denoted as Su(kk). Band energies are calculated of both the positive half spectral energy density of the reverberator S(kk) and the positive half spectral energy density of the unit impulse Su(kk). Band energies can be calculated as where ^ _^^^ and ^ _^^^^ are the lowest and highest bin index belonging to band k, respectively. The band bin indices can be obtained by comparing the frequencies of the bins to the lower and upper frequencies of the band. The reproduced ^^^ _^^^ ⁽ ^ ⁾ of the reverberator output at the frequency band k is obtained as ^^^ _^^^ ⁽ ^ ⁾ = ^(^)/^^(^) The target linear magnitude response for GEQRDR can be obtained as rdrFilterTargetResponse(k) = sqrt(RDR(k)) / sqrt(^^^ _^^^ ⁽ ^ ⁾ ) where RDR(b) is the linear target RDR value at band k. GontrolGain(k) = 20*log10(rdrFilterTargetResponse(k)) is input as the target response for the graphic equalizer design routine as in the references cited above (the control gains). The RDR filter target response (control gains for the graphic EQ design routine) can also be obtained directly in the logarithmic domain as Then as shown by 1407 based on the predelay and delay line lengths the delay of the predelay line is determined. The length of the predelay line ^^^^ can be adjusted based on the input predelay ^. The input predelay is converted to samples and the length of the shortest delay line is subtracted from it. This can be set as the length ^^^^. This will cause the first impulses from the FDN to occur after time ^. In some other embodiments, the diffuse portion of the FDN is set to start after time ^. In this case the ^^^^ can be shorter and can be set based on an estimate of the time at which the FDN output becomes diffuse and by setting the predelay line such that the desired time can be obtained. Furthermore based on the loudspeaker setup and directional gains the output channel gains are determined as shown by 1409. In these embodiments the RT60 time can be different for different spatial directions. The output channel gains are adjusted based on the directional gains obtained from the analysis of the SRIR in the directional gains determiner. The loudspeaker setup directions are compared to directions related to directional gains. In a simple example there is a one-to-one correspondence between the loudspeaker setup directions and the directions used in the beamforming step of the directional gains determiner. In this case the output channel gains ^ _^ can be set equal to the corresponding directional gain. If the directions are not the same then the output channel gain ^ _^ can be set based on ^ _^,^^ the closest directional gain ^ _^ = ^ _^ = 10 ^{^^} . The reverberator parameters can then be output as shown by 1411. With respect to Figure 15 is shown a schematic view of an example binaural renderer 207 according to some embodiments. The binaural renderer is configured to receive the directional reverberant audio signals 212 ^ _^^^ (^, ^) and the loudspeaker setup 204 ^ _^^ (^), ^ _^^ (^). The binaural renderer 207 in some embodiments comprise HRTF processors 1501, 1511, 1521 (which can be parallel or series HRTF processors and which based on the loudspeaker setup 204 apply an HRTF filter pair ℎ _^^^ (^, ^ _^^^ , ^) (where ^ is the time index of the filter coefficients and ^ _^^^ , is the index of the binaural channels) for the loudspeaker channel ^. In this example there are 3 processors shown in Figure 15, however there would be for N channels N processors where the (channel) processors receive their respective channel directional reverberant audio signal and is configured to output a respective channel reverberant binaural signals. Using the HRTF filter pairs ℎ _^^^ (^, ^ _^^^ , ^), reverberant binaural audio signals 1502, 1512, 1522 can be determined for the channel of the directional reverberant audio signals by where ^ denotes convolution (the filtering may also be performed in the frequency domain in some implementations instead of time-domain convolution). The reverberant binaural audio signals for the channel 1502, 1512, 1532 can be passed to a binaural signal combiner 1503 which is configured to combine the signals to generate the reverberant binaural audio signals 214. In other words the binaural signals for the different loudspeaker channels ^ are summed in the binaural signal combiner 1503 by yielding the reverberant binaural audio signals 214 ^ _^^^ (^, ^ _^^^ ) which are output. With respect to Figure 16 is shown a flow diagram of the operation of the example binaural renderer 207 shown in Figure 15. Thus for example is shown the operations of: Obtaining or otherwise receiving a loudspeaker setup, and directional reverberant audio signal for the channel as inputs as shown by 1601. Then, having obtained the loudspeaker setup and directional reverberant audio signal for the channel, an HRTF based on the loudspeaker setup can be applied to the channel directional reverberant audio signal as shown by 1603. Then combine the generated reverberant binaural audio signals to generate combined channel reverberant binaural audio signals as shown by 1605. Finally output the combined channel reverberant binaural audio signals as shown by 1607. In some embodiments there can be multiple SRIRs captured from a room. In this case, the analysis for directional decay and other reverberation parameters is performed as described above for the SRIRs. The analyzed parameters are associated to the corresponding positions and orientations in the room where the SRIRs have been captured. When the listener is being rendered a reverberated signal in the room, interpolation is applied to the determined parameters to obtain the reverberation parameters for this listening position and orientation. In a simple example, the parameters from the closest SRIR are used to the listener position. In other embodiments, interpolation between parameter values from two or more SRIRs are used. An example includes triangulating the positions spanned by the positions of the SRIRs and determining for the listener position the corresponding triangle of SRIR positions surrounding the listener position. The parameters from the triangle SRIRs can then be interpolated with suitable weights, for example, by using Vector-Base-Amplitude-Panning (VBAP) gains to the triangle positions. Any other suitable interpolation method can be used, for example, weighting the parameters of a SRIR by the distance of the listener to it and calculating a weighted sum of the parameter values. Similarly to above, in the case of binaural rendering in six degrees of freedom such that the listener can move in the space and even with a single SRIR measured in a room, the directional gains can be interpolated from the closest directional gains to the direction from which a certain output channel of the reverberator is reproduced. Such interpolation can be applied both when head tracking is applied to the reverberator output channel positions and when it is not applied. With respect to Figure 17 is shown schematically an example system where the embodiments are implemented in an encoder device 1901 which performs part of the functionality; writes data into a bitstream 1921 and transmits that for a renderer device 1941, which decodes the bitstream, performs reverberator processing according to the embodiments and outputs audio for headphone listening. Figure 17 for example shows apparatus, and specifically the renderer device 1941, which is suitable for performing spatial rendering operations. The encoder side 1901 of Figure 17 can be performed on content creator computers and/or network server computers. The output of the encoder is the bitstream 1921 which is made available for downloading or streaming. The decoder/renderer 1941 functionality runs on end-user-device, which can be a mobile device, personal computer, sound bar, tablet computer, car media system, home HiFi or theatre system, head mounted display for AR or VR, smart watch, or any suitable system for audio consumption. The encoder 1901 is configured to receive the virtual scene description 1900 and the audio signals 1904. The virtual scene description 1900 can be provided in the MPEG-I Encoder Input Format (EIF) or in other suitable format. Generally, the virtual scene description contains an acoustically relevant description of the contents of the virtual scene, and contains, for example, the scene geometry as a mesh or voxel, acoustic materials, acoustic environments with reverberation parameters, positions of sound sources, and other audio element related parameters such as whether reverberation is to be rendered for an audio element or not. The encoder 1901 furthermore in some embodiments comprises a scene encoder 1913 configured to obtain the virtual scene description 1900 and generate suitable encoded scene parameters. In the embodiments described herein the scene parameters are encoded into a bitstream payload. The encoder 1901 further comprises a MPEG-H 3D audio encoder 1914 configured to obtain the audio signals 1904 and MPEG-H encode them and pass them to a bitstream encoder 1915. The encoder 1901 furthermore in some embodiments comprises a bitstream encoder 1915 which is configured to receive the output of the scene encoder 1913 and the encoded audio signals from the MPEG-H encoder 1914 and generate the bitstream 1921 which can be passed to the bitstream decoder 1941. The bitstream 1921 in some embodiments can be streamed to end-user devices or made available for download or stored. The decoder 1941 in some embodiments comprises a bitstream decoder 1951 configured to decode the bitstream. The decoder 1941 further can comprise a scene decoder 1953 configured to obtain the encoded scene parameters and decode these in an opposite or inverse operation to the scene encoder 1913. The room dimensions and SRIR generator 1971 is configured to generate and pass the room dimensions and SRIR to the reverberation parameter determiner 1953 and the directional gains determiner 1955. The reverberation parameter determiner 1953 and direction gains determiner 1955 are the same as described above and configured to pass their outputs to the reverberation controller 1955. The room dimensions and SRIR generator 1971 can perform measurements or scanning on a user device to obtain the room dimensions and the SRIR or it can connect to a network server apparatus to request such information for the current room. Furthermore the head pose generator 1957 receives information from a head mounted device or similar and generates head pose information or parameters which can be passed to the reverberator controller 1955, binaural renderer 1962 and the direct sound binaural renderer 1963. The decoder 1941, in some embodiments, comprises a reverberator controller 1955 which also receives the output of the scene decoder 1953 and generates the reverberation parameters for initializing the reverberator 1961 in a manner as described above. The decoder 1941 in some embodiments comprises a MPEG-H 3D audio decoder 1954 which is configured to decode the audio signals and pass them to the (FDN) reverberator 1961 and direct sound processor 1965. The decoder 1941 furthermore comprises (FDN) reverberator 1961 initialized by the reverberator controller 1955 and configured to implement a suitable reverberation of the audio signals. The output of the (FDN) reverberator 1961 is configured to output to a binaural signal combiner 1967. Additionally the decoder/renderer 1941 comprises a direct sound processor 1965 which is configured to receive the decoded audio signals and configured to implement any direct sound processing such as air absorption and distance-gain attenuation and which can be passed to a direct sound binaural renderer 1963 which with the head orientation determination (from a suitable sensor) can generate the direct sound component which is passed to a binaural signal combiner 1967. The binaural signal combiner 1967 is configured to combine the direct and reverberant parts to generate a suitable output (for example for headphone reproduction). Although not shown, there can be various other audio processing methods applied such as early reflection rendering combined with the proposed methods. Although in Figure 17 the interface to the decoder/renderer 1941 is depicted to be the output from the Room dimensions and SRIR generator 1971 other interfaces are possible. In an alternative embodiment one or both of the Reverberation parameter determiner 1953 or Directional gains determiner 1955 can be located outside the Decoder/Renderer 1941. In this case, there can be an interface defined between the Decoder/Renderer 1941 via which the Reverberation parameters and/or Directional gains can be provided. An example is a listening- space-description interface which can be a file or other suitable interface, which can carry the room dimensions and SRIR (if Reverberation parameter determiner 1953 or Directional gains determiner 1955 are inside the Decoder/Renderer 1941) or room dimensions and Reverberation parameters and directional gains (if Reverberation parameter determiner 1953 or Directional gains determiner 1955 are outside the Decoder/Renderer 1941). With respect to Figure 18 an example electronic device which may be used as any of the apparatus parts of the system as described above. The device may be any suitable electronics device or apparatus. For example in some embodiments the device 2000 is a mobile device, user equipment, tablet computer, computer, audio playback apparatus, etc. The device may for example be configured to implement the encoder or the renderer or any functional block as described above. In some embodiments the device 2000 comprises at least one processor or central processing unit 2007. The processor 2007 can be configured to execute various program codes such as the methods such as described herein. In some embodiments the device 2000 comprises a memory 2011. In some embodiments the at least one processor 2007 is coupled to the memory 2011. The memory 2011 can be any suitable storage means. In some embodiments the memory 2011 comprises a program code section for storing program codes implementable upon the processor 2007. Furthermore in some embodiments the memory 2011 can further comprise a stored data section for storing data, for example data that has been processed or to be processed in accordance with the embodiments as described herein. The implemented program code stored within the program code section and the data stored within the stored data section can be retrieved by the processor 2007 whenever needed via the memory-processor coupling. In some embodiments the device 2000 comprises a user interface 2005. The user interface 2005 can be coupled in some embodiments to the processor 2007. In some embodiments the processor 2007 can control the operation of the user interface 2005 and receive inputs from the user interface 2005. In some embodiments the user interface 2005 can enable a user to input commands to the device 2000, for example via a keypad. In some embodiments the user interface 2005 can enable the user to obtain information from the device 2000. For example the user interface 2005 may comprise a display configured to display information from the device 2000 to the user. The user interface 2005 can in some embodiments comprise a touch screen or touch interface capable of both enabling information to be entered to the device 2000 and further displaying information to the user of the device 2000. In some embodiments the user interface 2005 may be the user interface for communicating. In some embodiments the device 2000 comprises an input/output port 2009. The input/output port 2009 in some embodiments comprises a transceiver. The transceiver in such embodiments can be coupled to the processor 2007 and configured to enable a communication with other apparatus or electronic devices, for example via a wireless communications network. The transceiver or any suitable transceiver or transmitter and/or receiver means can in some embodiments be configured to communicate with other electronic devices or apparatus via a wire or wired coupling. The transceiver can communicate with further apparatus by any suitable known communications protocol. For example in some embodiments the transceiver can use a suitable universal mobile telecommunications system (UMTS) protocol, a wireless local area network (WLAN) protocol such as for example IEEE 802.X, a suitable short-range radio frequency communication protocol such as Bluetooth, or infrared data communication pathway (IRDA). The input/output port 2009 may be configured to receive the signals. In some embodiments the device 2000 may be employed as at least part of the renderer. The input/output port 2009 may be coupled to headphones (which may be a headtracked or a non-tracked headphones) or similar. In general, the various embodiments of the invention may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the invention is not limited thereto. While various aspects of the invention may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof. The embodiments of this invention may be implemented by computer software executable by a data processor of the mobile device, such as in the processor entity, or by hardware, or by a combination of software and hardware. Further in this regard it should be noted that any blocks of the logic flow as in the Figures may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD. The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processors may be of any type suitable to the local technical environment, and may include one or more of general-purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi-core processor architecture, as non-limiting examples. Embodiments of the inventions may be practiced in various components such as integrated circuit modules. The design of integrated circuits is by and large a highly automated process. Complex and powerful software tools are available for converting a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate. Programs, such as those provided by Synopsys, Inc. of Mountain View, California and Cadence Design, of San Jose, California automatically route conductors and locate components on a semiconductor chip using well established rules of design as well as libraries of pre-stored design modules. Once the design for a semiconductor circuit has been completed, the resultant design, in a standardized electronic format (e.g., Opus, GDSII, or the like) may be transmitted to a semiconductor fabrication facility or "fab" for fabrication. As used in this application, the term “circuitry” may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) combinations of hardware circuits and software, such as (as applicable): (i) a combination of analog and/or digital hardware circuit(s) with software/firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and I hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device. The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal ) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM). As used herein, “at least one of the following: <a list of two or more elements>” and “at least one of <a list of two or more elements>” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements The foregoing description has provided by way of exemplary and non- limiting examples a full and informative description of the exemplary embodiment of this invention. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this invention will still fall within the scope of this invention as defined in the appended claims.