Pioneer C90 preamp and M90 Poweramp

Pioneer introduced the M-90 Reference Power Amplifier in 1987, to be used in conjunction with the C-90 Reference Control Amplifier. In the January 1987 issue of Stereo Review that ran the "Not Evolutionary-Revolutionary" advertisement, here is what Pioneer said about the M-90:

"The M-90 is a superb high-power stereo amplifier, utilizing dual-mono construction. It is conservatively rated at 200 W/CH into 8 ohms and delivers 800 W/CH of dynamic power at 2 ohms. The wide dynamic range of the digital sources can now be reproduced effortlessly, with any loudspeakers. The M-90's high current capacity of 47 amps can handle the challenge of the most complex speaker loads. To further enhance S/N ratio and channel separation, relay-operated electronic switches and a long shaft volume control keep the length of signal paths down to a minimum. Why include a high quality volume control on a power amp? To pursue the straight wire-with-gain philosophy when using a CD player connected directly. Pure sound, redefined."

The M-90 was virtually distortion-free, having only 0.003% THD from 20-20K Hz @ 8 ohms, and had a S/N ratio of 125 dB! (See the complete specifications at bottom of page.) The M.S.R.P. for the M-90 was $950.00. It was superseded by the M-91 in 1989.

Rate This equipment is not easy, we are faced with very beautiful objects, rather famous, and having heard many good things about these objects, it could be strongly determined .......But if we want to tell the truth, when considering an appliance and fair to take account of these things that make a great machine ....The sound is very accurate, maybe not too long at the bottom, but with a dynamic that is scary ..According to me and tried to make a device, have changed considerably in those years, where the boom boom was very fashionable ..This is a device in many ways modern and current, fast, clear sound and clear, and apologize if I repeat myself, in a way remarkable. The bass is felt as a blow dry, all the power delivered in a split second, just as we tend to build amplifiers nowadays.