Need to learn about Audio Research

@fsonicsmith

I always thought the "straight wire with gain" is one of the most meaningless cliche's among the thousands in audio. Two preamps can be "straight wires with gain" and yet sound completely different, particularly if one if solid state and one is tubed. 

This phrase was coined by Quad founder Peter Walker, who built valve and solid state amplifiers and separate pre-amplifiers, as well as electrostatic loudspeakers.

Far from a cliche, it was his design goal for power amplifiers.  On the other hand, his pre-amplifiers had multiple controls to allow the user to ameliorate playback of poor recordings, and were never "straight wires with gain".

He was incensed when a journalist suggested his valve designs sounded different from his solid state designs, and organised the best controlled comparison I have ever read about.  These is a topic here Audiogon Discussion Forum

Peter Walker (Quad) did a study comparing the sound of his own amps (Quad II and 303) tubes vs. transistors. He used RTR dubs of master tapes and presumably Quad ESL's. The two amps are well matched power-wise. It was a very thorough listening comparison using a written scoring system. He and his panelists could not distinguish between the two, until driven into clipping. It was a blind test - the amps were labeled A and B. The music chosen was various selections presumably from Decca and EMI masters. This is the most thorough test comparing tubes and SS that I am aware of! The listening panelists were recording professionals and musicians. Peter Walker's conclusion was that all well-designed amps operated below clipping will sound the same. I will point out that this was not your typical "get together in a basement with your buddies for a few hours swapping cables between two amps". It was a carefully planned and set up experiment (matched levels) - now forgotten and unaware of by today's hobbyists.

I cannot find the original paper, but three Quad models were involved (add the 405). The speakers were Yamaha, at the insistence of the journalist who later withdrew from the listening sessions - and audio journalism!  This listening panel comprised renowned British audiophiles and the tests were staged over two days.  Each blind test randomly compared two amplifier types (which could also be the same) and each panel member was asked to rate the sound quality the same, better or worse.  The results were statistically inconclusive for all panel members - nobody could reliably hear a real difference.  The amplifiers had much lower distortion than the speakers!