Sherbourn 5/1500A Five-Channel Amplifier HT Labs Measures
This graph shows that the 5/1500A's left amplifier channel, with two channels driving 8-ohm loads, reaches 0.1% distortion at 181.3 watts and 1% distortion at 210.2 watts. Into 4 ohms, the amplifier reaches 0.1% distortion at 317.1 watts and 1% distortion at 356.4 watts. Using the RCA input, 83.0 millivolts was required to produce an output of 2.83 volts into an 8-ohm load, indicating an overall gain of 30.65 decibels. Using the XLR input, 166.0 mV produced an output level of 2.83 volts into an 8-ohm load, indicating an overall gain of 24.64 dB. With all channels driven into 8-ohm loads, the amp reaches 0.1% distortion at 175.6 watts and 1% distortion at 201.9 watts.
The amplifier's frequency response was +/-0.18 dB from 20 hertz to 20 kilohertz. The response dropped to -0.60 dB at 10 Hz and to -0.70 dB at 50 kHz. THD+N from the amplifier was less than 0.036% at 1 kHz when driving 2.83 volts into an 8-ohm load. Crosstalk at 1 kHz driving 2.83 volts into an 8-ohm load was -85.85 dB left to right and -86.36 dB right to left. The signal-to-noise ratio with 2.83 volts driving an 8-ohm load from 10 Hz to 24 kHz with "A" weighting was -90.25 dBrA using the RCA input and -98.43 dBrA using the XLR input.—AJ