To record the amplitude value of an input signal surely and accurately by avoiding the occurrence of an overflow and a deterioration in resolution.

The recording apparatus comprises a signal amplification section 2 for amplifying the input signal S1 with a predetermined amplification rate and a control section 4 for setting either one of a plurality of amplification rates as an amplification rate of the signal amplification section 2 and storing the amplification rate Dg indicating the amplification rate and voltage value data Dv indicating the voltage value of the amplified input signal S2 in a 16-bit manner in a storage section 5. When the absolute value of the voltage value of the voltage value data Dv reaches an upper limit value representable in a 16-bit manner or a first predetermined value in the vicinity thereof, the control section 4 sets an amplification rate which is lower than the set amplification rate as the amplification rate of the signal amplification section 2. When the absolute value of the voltage value of the voltage value data Dv falls below an upper limit value in an amplification rate which is higher than the set amplification rate out of the plurality of amplification rates or a second predetermined value in the vicinity thereof, the control section 4 sets the higher amplification rate as the amplification rate of the signal amplification section 2.