This is not like the cheap Sherwood items that were sold by Richer Sounds in the past, this is from before they started doing that, its a serious bit of kit with extremely good sound quality.
Please see below for the specifications, or see the photos for some shots of the service manual.
Power output per Channel
IEC Standard, at 63-12,500 Hz into 8 ohms ............................................ 220W
at 63-12,500 Hz into 4 ohms ................................................................... 340W
Dynamic Power output per Channel
into 8 ohms ................................................................................... 270W
into 4 ohms .................................................................................. 450W
into 2 ohms ................................................................................... 650W
Total Harmonic Distortion, -6 dB Rated Output Power
at 1 kHz into 8 ohms ........................................................................ 0.007%
at 10 kHz into 8 ohms ....................................................................... 0.009%
Damping Factor at 200W 50 Hz, into 8 ohms .............................................. 150
Frequency Response, -3 dB .................................................................. 5 Hz-150 kHz
Signal to Noise Ratio, "A" wtd/unwtd (at 22 kohm Terminated, Reference 0 dB)
at 200W into 8 ohms ........................................................................ 110/90 dB
at 1W into 8 ohms ........................................................................... 90/80 dB
Input Sensitivity at 200W, 1 kHz into 8 ohms .............................................. 1000mV
Channel Separation at 200W into 8 ohms
22 kohms Terminated at 1 kHz ............................................................ 80 dB
22 kohms Terminated at 10 kHz .......................................................... 70 dB