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Peter Walker ( Quad) on design

Yep that's about normal for designing amps and much the same as I do it. One channel will be built as a lash up on breadboard in order to get it right, do all the changes required to achieve the bandwidth, distortion spec and stability required. This can take weeks. Then a two channel version will be built on strip board and this tested for any interaction between channels, unexpected issues due to layout changes etc and any small tweaks carried out. Only then do you get to hear it for the first time!! There's no other way to do it really...
 
I am lucky it will sound strange, but I hear the design in my head first, then go for a PCB and 99% of the time it work first time except for a few tube designs, now swimming of S.O.S. Pier.
 
"We never sit down and listen to a music record through an amplifier in the design stage".

There is nothing unusual about this!

It is about testing what you have designed meets the designed specs, i.e. gain, bandwidth, distortion, noise, signal to noise, circuit stability and of course CE regulations at this phase of the development. Further tests would be to see if any variation in components or alternative manufacturers parts would effect the results or design. When the designer is happy with this the next phase would be to see how it interacts with other equipment (including other manufacturers electronics) and this is where some listening tests might come in. When all that has been done the designer, or owner of the company might want to "voice" or fine tune the unit to get the best result. This is more typically done today. There are a number of other tests that would need to be done, assuming what was being produced was going to different parts of the world...

Don't forget that when Peter Walker was involved with QUAD there was very little choice in what parts could be used. It has only been in the last 30 years where great advancements have been made in construction of electronic components, where some have been specifically designed for audio use.
 
Also worth noting that Peter Walker was very much involved in the various groundbreaking ‘live vs. recorded’ public dems of the late-50s with Gilbert Briggs etc so was very happy for his equipment to be subjectively appraised. It is all to easy to take certain quotes out of context without any real understanding of the person or company in question.
 
p.w worked with a prof Roberts/Sheffield university . my tutor in the 70s robo and peter did a lot of listening , fact . prof gave the 57s design as a lead to his subject electrostics , i still have his book in the loft somewhere
 
Peter Walker's grandson works with me (and lived with him growing up() and has given me a good overview of many things Quad.
 
"We never sit down and listen to a music record through an amplifier in the design stage".
There is nothing unusual about this!

Indeed. I recall a conversation with an ex Linn design engineer re working on the Karik/Numerik (I think).

Ground up design, all measured superbly, project going great until they listened to it. Oops.

That triggered a lot of investigation, more measurements and some fairly fundamental changes in the final design.
 


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