Objectivist or Subjectivist? Give Me a Break

[jkeny]

Tim,
Ethan can't show a 80dB null while taking the loudspeaker & it's interactions with the amplifier's output stage into account. His statement that SS amplifers are "close to ideal" is his attempt at dodging this well known source of differences between amplifiers. He was asked to put a value on this closeness to ideal & give some real world examples of such SS amplifers.

 

[jkeny]

It is now numbingly pedantic. A bump in the noise floor.
Tim

Tim, it's a pity when challenging/searching questions are asked about stated objective measurements, you claim pedancy. Does this mean you would prefer a sort of "fuzzy" unchallenged objectivism with measurements that may/may not mean anything?

 

[Raffles]

If two devices have the same level and spectrum of THD and IMD, then they will sound the same.

Is that necessarily true? I think I could design two devices with arbitrarily identical THD and IMD that would still sound different. An example that springs to mind would be one of the old DBX type noise reduction devices. The compressor part basically varied its gain in response to input level with a time constant of a fraction of a second. I suggest that in a test using a steady signal, you might get the same THD and IMD results regardless of the setting of the compression factor, but it would sound completely different with a 2:1 compression setting compared to a 1:1 setting*.

Edit: *when listening to the compressor output directly.

 

[Phelonious Ponk]

Tim,
Ethan can't show a 80dB null while taking the loudspeaker & it's interactions with the amplifier's output stage into account. His statement that SS amplifers are "close to ideal" is his attempt at dodging this well known source of differences between amplifiers. He was asked to put a value on this closeness & give some real world examples of such SS amplifers.

Yeah, maybe. Or maybe he's trying to tell you that if an amplifier is well-engineered and the speaker has a reasonably normal impedance curve, these "well-known sources of differences" should fall somewhere between inaudible and insignificant. Can you find speakers that will significantly, audibly change the performance of well-designed amps? I'm sure you can. And I'd blame the speaker for that problem and choose something better. Unless you're saying that it's not a problem isolated to oddball designs, non-standard output, wacky impedance curves, etc, etc...? Are you saying that you can buy a good amp, like a Byston or a Krell or even an Emotiva, that is designed to perform consistently with conventional high-end speakers, that is deliberately over-engineered to compensate for the varying loads of such speakers, and still that amp's performance will signficantly, audibly change if you switch from a Magico to a Revel?

Why would you tolerate such crappy performance from such expensive equipment? To embrace this dark vision of bad performance you have, I'll need to see measurement of amps, under varying loads, demonstrating this phenomenon. And I really hope no one can come up with them, because this should be the rare exception, and when it occurs, something should be extracted from the signal chain before it breeds.

Tim

 

[Phelonious Ponk]

Tim, it's a pity when challenging/searching questions are asked about stated objective measurements, you claim pedancy. Does this mean you would prefer a sort of "fuzzy" unchallenged objectivism with measurements that may/may not mean anything?

No, I really enjoy the fuzzy unchallenged subjectivism totally unrestricted by any measurements at all.

 

[jkeny]

No, I really enjoy the fuzzy unchallenged subjectivism totally unrestricted by any measurements at all.

No measurements are better than misleading & unsubstantiated measurements

 

[Phelonious Ponk]

No measurements are better than misleading & unsubstantiated measurements

That was a joke, John. It's the other post that needs an answer.

Tim

 

[jkeny]

Well, Tim, Ethan is making the claim of near-ideality of real-world amplifiers (& therefore minimum effect from speaker loads) - it is up to him to state how close this is to ideal & give some examples. But one thing is sure, he can't produce a null measurment of 80dB for this steup & this was his claim - that measurments can prove two amplifiers are identical sounding. Case closed on this particular claim!

 

[Phelonious Ponk]

Well, Tim, Ethan is making the claim of near-ideality of real-world amplifiers (& therefore minimum effect from speaker loads) - it is up to him to state how close this is to ideal & give some examples. But one thing is sure, he can't produce a null measurment of 80dB for this steup & this was his claim - that measurments can prove two amplifiers are identical sounding. Case closed on this particular claim!

Then let's open the case for the counter claim if you don't mind? This well-known variable you spoke of, in which quality amplifiers' performance varies quite audibly under different speaker loads? Got any measurements? What happens to those amps when the load changes? And if you have not looked at measurements showing clear changes in the performance of these amps under different loads, how is this variable well-known, known, or even suspected? Can't trust your ears on this one; you changed speakers. Of course it sounds different.

Tim

PS: I'd be happy to start a thread just for this discussion, if you prefer.

 

[jkeny]

........
PS: I'd be happy to start a thread just for this discussion, if you prefer.

Yes, that's best!

 

[JackD201]

The other replied, "001001 000010 111001"

Tim

Bwahahahahahaha! You made my day and I haven't even had my cup of coffee yet!

 

[opus111]

If two devices have the same level and spectrum of THD and IMD, then they will sound the same.

Does this claim apply for any two possible devices, or only devices you've encountered personally?

 

[NorthStar]

---Methinks that Ethan is the smart guy here; as no one responded to his earlier question/request/suggestion regarding the comparison of three music 'passes'. He posted the links; just go back few pages.

Then maybe he'll talk with people who truly want to. He ain't wasting his words no more.

I would if I was more knowledgeable in that specific matter, but I'm not.

* John, I believe you can improve, with perhaps some facts about the 80dB null measurements impossibility?

 

[JackD201]

---Methinks that Ethan is the smart guy here; as no one responded to his earlier question/request/suggestion regarding the comparison of three music 'passes'. He posted the links; just go back few pages.

Then maybe he'll talk with people who truly want to. He ain't wasting his words no more.

I would if I was more knowledgeable in that specific matter, but I'm not.

* John, I believe you can improve, with perhaps some facts about the 80dB null measurements impossibility?

Forgive me if I disagree. In my opinion there's a lot lacking in his experiments, particularly on the audibility side to back up his conclusions. His sample sizes don't cut it for me and I'm far more lenient than a Stat 101 professor.

 

[NorthStar]

---That is perfectly appropriate Jack, as Ethan ain't the last "archipel'' from all the vast oceans.

He has some good points, knowledge on room acoustics, and he's an experimenter with measurements and analyses.
He can teach few, and perhaps can 'approfondir' some too with concrete facts and proven methods (according to some of his 'compatriotes').

But it often seems quite 'lively' when he's into it. :b
He certainly raises few hairs on the back of few members here. :b
All is good. :b

 

[JackD201]

Well, I won't begrudge his efforts and experience except to say he holds no monopoly of the same. Let's just say, I'm wary of anybody that professes to have figured everything out. Not even Einstein, Newton or Hawking did that.

 

[NorthStar]

Well, I won't begrudge his efforts and experience except to say he holds no monopoly of the same. Let's just say, I'm wary of anybody that professes to have figured everything out. Not even Einstein, Newton or Hawking did that.

-----Sigmund? ...Freud.

 

[JackD201]

About Cocaine perhaps. Too bad for his Morphine addicted buddy, he was wrong.

 

[jkeny]

---Methinks that Ethan is the smart guy here; as no one responded to his earlier question/request/suggestion regarding the comparison of three music 'passes'. He posted the links; just go back few pages.

You mean he abandoned his claim about objective measurement "proving" anything & resorted to subjective listening test for a specific piece of music on a specific playback/recording setup and he is trying to draw generalisations from this specific test.

Then maybe he'll talk with people who truly want to. He ain't wasting his words no more.

Are you his apologist or his public relations wing ?

I would if I was more knowledgeable in that specific matter, but I'm not.

* John, I believe you can improve, with perhaps some facts about the 80dB null measurements impossibility?

Ethan has stated that the 80dB null is theoretical & hasn't wavered from that, why not ask him for the facts?

PS: Yes I see Jack has made exactly the same points as I. I'll say one further thing, many people show a preferrence for incomplete, untrustworthy, inconclusive measurements rather than remaining open-minded about matters. I guess it's not surprising - we seem to crave certainty about matters & uncertainty is uncomfortable. But in dealing with the real world uncertainty is everywhere, so we have to be realistic & face it as we find it rather than create religious beliefs about it.

 

[rbbert]

I'm pretty sure a -80 dB null for an amplifier/cables/speaker combo (input to output) would indicate two systems were indistinguishable.