Here's a fun little quote which I snipped from the following web page:
Technical Background of Pass Labs Xs phono - by Wayne Colburn, designer
Yes, dear reader, there does exist a Pass Labs product of mind boggling complexity. And people like the way it sounds.
Technical Background of Pass Labs Xs phono - by Wayne Colburn, designer
These circuit boards are dual mono in a side-by-side configuration, just like the power supply with its twin boards and 120-watt toroids. We have multiple stages of regulation with electrolytic and film capacitors, in an all discrete cascade circuit. I hate to say it but even the pass transistors [in the regulators] were selected for their sonic performance. They matter and not just a little.
All this is enclosed in heavy, dual aluminum chassis for stability, shielding and to hold the user interface. Three inputs are selectable with loading from 30-47K Ohms, 100-750 PF and variable gain, plus nonvolatile memory for the loading settings. A front panel mute is available, as is a 20 Hz RIAA high pass.
Yes, the XS Phono costs more than the XS Preamplifier ($38,000) but it uses 1500 parts on 13 circuit boards and sounds awesome, plus you can use it more hours a day than your Aston Martin, unless you have a long commute.
Yes, dear reader, there does exist a Pass Labs product of mind boggling complexity. And people like the way it sounds.
Manufacturers historically have targeted low distortion and high power in order to drive a wide variety of loudspeakers. This race to the lowest distortion possible and wide compatibility has been going on for decades, which began at and ended the tube era.
Nelson figured a long time ago that there are things that matter in perception: these are things that can and cannot be measured. Also, most amplifier designs are not new, including Nelson’s. It’s just how they are implemented.
When I design a loudspeaker I do not fix everything in the summed response because it’s both unnecessary and generates compromises. Also, the laws of engineering are much easier to deal with than economics.
Nelson figured a long time ago that there are things that matter in perception: these are things that can and cannot be measured. Also, most amplifier designs are not new, including Nelson’s. It’s just how they are implemented.
When I design a loudspeaker I do not fix everything in the summed response because it’s both unnecessary and generates compromises. Also, the laws of engineering are much easier to deal with than economics.
If you understand engineering than you know scaling is not a linear but a logarithmic curve. If you look at a class A design it tops out at 30-40 watts any of your FW design fall in this territory. if you try to get a 100 watt class A amp it will cost a fortune, run ridiculously hot, and weigh a ton. When you are trying push 100+ watts out of a class a/ b design there complexities grow and the parts count follows. Just look at the diy Wolverine amp, it is not designed to be commercial product (no building in stupid protection, or ridicules extra bells and whistles) and it has a pretty high parts count and complexity. Ad a nice case and a UL approval and your close to the price of a commercial product.
Nelson understands (as I understand him) that a good deal of listeners prefer a sound that is, let's say, "enhanced" by low order distortion. He is a member of this club after all. IMO this also explains why there is a group of people who strongly feel that vinyl sounds so much better than e.g. digital music. It's the distortion! Low orders sound good, and high orders sound bad (it's the truth). So Nelson prefers to create amplification that has such a sonic profile baked into the amp, even sometimes going so far as to make this characteristic "adjustable" via a front panel knob. In this case, distortion is not a dirty word but rather it is a feature, not a bug.
Believe me, these things CAN be measured. There is no magic. It's just that human perception and hearing doing their thing, and maybe there is some confirmation bias thrown in there for good measure.
There is much more to "good sound" than making distortion and output impedance go to zero, which is what most modern amplification aims to do. As a DIY loudspeaker builder my opinion is that the "magic" is in the speakers and their room interaction and not in "distortion enhanced" amplification. This is despite the fact that moderate distortion and output impedance tends to improve some types of speakers so it has it's uses for sure.
My 100W of Class A amplification only cost me 2 FW clones and weigh twice as much as 1 FW clone. And after living with them for a couple years, total overkill. Looking forward to making some littler 25-30W balanced monoblocks with FW flavor.
Maybe ... maybe not.
It depends a lot on the history or mystique behind it.
Nothing can be simpler than 10 component SE amps using single DHT as a power device, and then they
command top dollars.
And any effort to "modernize/improve" them fails, I mean commercially.
True, but the market for SE DHT amps is small. There are a lot more high dollar high parts count amplifiers than high dollar low parts count amplifiers available in the marketplace.
Yes, varying levels of negative H2 as an example…that’s why I said some things can be. I have a listening room and workshop full of DIYFW, tube amps and Choky designs. Just trying to keep the discussion general here…
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Four hours later we have a completely rebuilt (new joysticks and all) Xbox x/s controller. Now where do I send the invoice? Two technicians @ $55 each totals $440.
There's also the element of seeing what the competition is producing and trying to beat it.
It's the battle of the specs.
Yes.
A lot of the battles run around microscopic improvements, which can be measured and printed on a spec sheet or advertisement, no doubt, but are inaudible to the naked ear.
Distortion is an important factor but ..... does 0.000001% distortion sound 1000 times better than 0.001%?
Not so sure.
We see threads arguing distortion and noise 120 to 140dB below signal level.
Nice on a Philosophical level.
On a practical level?
Again, not so sure.
A lot of the battles run around microscopic improvements, which can be measured and printed on a spec sheet or advertisement, no doubt, but are inaudible to the naked ear.
Distortion is an important factor but ..... does 0.000001% distortion sound 1000 times better than 0.001%?
Not so sure.
We see threads arguing distortion and noise 120 to 140dB below signal level.
Nice on a Philosophical level.
On a practical level?
Again, not so sure.
Having about 50 amplifiers, so far i found no correlation between sound quality and distortion. Those with extremely low distortion do not necessarily sound better.
Same applies to preamps.
Issue may be that there are other parameters than simple thd figure, or issue is even more complex...what sounds good or better is totally subjective and we all preffer different sound.
If i select low distortion pre with low distortion amp, i may end up with borring uninvolving sound. Sign is that i am not willing to listen to the system for long.
After swapping amps and pre with more distortion, and anormous amount of time comparing and evaluating, i arrive at sound that pleases me. Gives me chills, bring tears in my eyes, make me listen every free time i have, gives me joy and satisfaction. Thanks to introduction of distortion.
Putting shades on mona lisa.
This is clearly of topic, but thats where it was headed. Amplifier manufacturers do not strive to produce amps with lowest distortion, if it was true, all amps would sound the same. Each has certain vision of sound. Thats why naim sounds different than parasound, than accuphase or bryston.
Each having different topology resulting in different flavour. Back to original question...yes, amplifiers can be made with few parts, but that would not be the sound manufacturers want to deliver.
Same applies to preamps.
Issue may be that there are other parameters than simple thd figure, or issue is even more complex...what sounds good or better is totally subjective and we all preffer different sound.
If i select low distortion pre with low distortion amp, i may end up with borring uninvolving sound. Sign is that i am not willing to listen to the system for long.
After swapping amps and pre with more distortion, and anormous amount of time comparing and evaluating, i arrive at sound that pleases me. Gives me chills, bring tears in my eyes, make me listen every free time i have, gives me joy and satisfaction. Thanks to introduction of distortion.
Putting shades on mona lisa.
This is clearly of topic, but thats where it was headed. Amplifier manufacturers do not strive to produce amps with lowest distortion, if it was true, all amps would sound the same. Each has certain vision of sound. Thats why naim sounds different than parasound, than accuphase or bryston.
Each having different topology resulting in different flavour. Back to original question...yes, amplifiers can be made with few parts, but that would not be the sound manufacturers want to deliver.
I think that it will take more components to make a more correct amp. By "correct" I mean a clinically better measuring amp. Such amp may or may not fit ones likings in ones current system.
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If memory serves, 1 of the "cures" for high THD was more negative feedback which in turn increased IM distortion, which is potentially more objectionable to the ear. This is 1 of the things we love about Papa's designs, not relying on specmenship but actually daring to listen and experiment. Of course all this would be for naught if Nelson didn't have an inquiring mind, great ears and serious chops!
It's ironic that tube fans are happy with 1% distortion (2H) yet solid staters are always wanting the op amps with distortion not far removed from a piece of wire with gain.
And hence my rule of thumb:
Objectivists measure things that cannot be heard, while subjectivists hear things that cannot be measured.
I agree with a lot of what you say here. In particular, distortion can be desirable snd preferred by some people. Even up to 3-5% with some kinds of music.
As for the last part, I think most famous designers fell in love with a certain design or approach and kept pushing it for a lifetime. They slowly became it, Dao De Jing-style.
Would they be able to tell their own kittens apart? They could. The rest of us would just see interesting experiments with variations of harmonic distortion.
There’s a lot of obsession involved in this.