Well, to be fair, Nelson (whom I have a lot of respect for) designed and publishes an H2 add-on that is meant to make the sound out of the amp different to what is going in. So he is not very concerned with accurate reproduction.
Getting mad about someone who measures stuff looks to me like shooting the messenger. Why do you care about measurements if you like the sound?
Jan
Yes he does, very honest in publishing results, and he doesn't mind a few % distortion. Because for him, his stated goal: "Its all entertainment".
His amps are pleasant to listen to, and the new H2 module that adds some 2nd harmonics makes it even more so to many people.
ASR comes from a complete different direction. They are looking for the most accurate reproduction, the original meaning of HiFi, to get a signal out of the amp that is an accurate replica from what goes in, and the measurements show ACA is not one of those, because it is not designed to. Nelson would be very well capable to design one if he wanted, I am sure!
So it's no use to get your panties in a knot over this, just enjoy your amp and let others enjoy their hobby. Why badmouth people just because they enjoy other things in life than you do!
Jan
His amps are pleasant to listen to, and the new H2 module that adds some 2nd harmonics makes it even more so to many people.
ASR comes from a complete different direction. They are looking for the most accurate reproduction, the original meaning of HiFi, to get a signal out of the amp that is an accurate replica from what goes in, and the measurements show ACA is not one of those, because it is not designed to. Nelson would be very well capable to design one if he wanted, I am sure!
So it's no use to get your panties in a knot over this, just enjoy your amp and let others enjoy their hobby. Why badmouth people just because they enjoy other things in life than you do!
Jan
With all due respect Jan, accurate reproduction is only meaningful to the listeners when measured at the acoustic output of which ASR never made.
We're talking about amplifiers here, not speakers. What ASR (in amps) is interested in is how accurate the amp output is with respect to the amp input.
Measurements tell you that. And it is important if you are looking for 'HiFi'. You can have the best speaker in the world, but if the amp messes up your signal, no speaker can fix that.
Jan
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There was another thread about this, and the ASR guy came over here to explain his point of view. Nobody listened but all condemned him. Very childish and immature show by the diyaudio members.
Jan
Of course Jan, but all amps need speakers to make any sound. When you do measure, a few fractional percent @ 1W of negative phased H2 produced by some papadesign amps including the ACA do reduce total THD of the acoustic output that gives a higher fidelity experience to us greedyboyz. 
Immature of Amir to condemn the ACA without making relevant comparison of measurement of the acoustic output.
Immature of Amir to condemn the ACA without making relevant comparison of measurement of the acoustic output.
For some reason, a few people strive to preserve the THD of the speakers they have as pristine as possible, probably they love that kind distortion so much. Perfectly fine but that is just one of many possible preferences, they have no right to impose their view onto others.
not saying that I read every reaction post, but what I know of that thread and original post - guy completely missed the point - ACA being more didactic piece/device than regular audio amplifier
that omission can be explained in 3 ways:
- deliberately malicious
-ignorance
-any possible combination (in amounts) of these two above
in one thing we agree - it wasn't worthy of proper reaction
here goes Papa's "Idon'tcare" Green
One of my biggest gripes with his 'reviews' is that if someone goes on that forum and says "This component sounds better than that one" everyone jumps on them shouting 'expectation bias' and 'double blind testing'. Yet he does his listening tests sighted and after he does his measurements. Somehow he is the only person on the planet that is exempt from expectation bias.
He also goes with the thinking that since he, and his group, listen at very high levels that if an amp or speaker can't handle playing at those levels then there is no reason for it to exist. Thus the testing is sometimes performed at levels that components weren't designed to operate.
And that is the reason I don't understand why they 'test' equipment that they know isn't designed around their goals. At that point it just seems they enjoy bashing products that aren't designed for them and working themselves into a negative frenzy about them.
There are plenty of amps and speakers that are designed around what they want but, for some strange reason, they won't be satisfied until none are built that don't meet their criteria. It actually annoys them that people enjoy amplifiers that aren't completely transparent.
Transparent amps need transparent speakers (which is non existent) to have completely transparent and faithful reproduction. They will be more annoyed when they learn that some of us are actually able to enjoy lower acoustic THD than anything that they praise. As Jan Didden said, why should we care what they think when Papa's stuff sound so good.
I don't think that is fair. He (Amir) said words indicating that it was a great didactic design for people learning to build amplifiers. It is even quoted in this thread above I think.
Edit: post # 6.
Jan
Jan,
Exactly where did Amir say this?
Copying the conclusion from his review:
"Conclusions
As a starter hobby amplifier to get some sound coming out of a speaker, with relatively few components, the Pass ACA Class A Amp does the job. Build it, have fun with it and then put it aside and get a proper amplifier. Amplifiers need to have a lot more power. And much less distortion. We are not even close here folks.
Do I need to tell you that I can't recommend the Pass ACA for hi-fi listening? I hope not."
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