To upgrade or not to upgrade, that is the question.

[MarkS]

Conventional wisdom in here says that all amps with test bench noise and distortion below X and a damping factor above Y will all sound the same driving every speaker made unless it is driven into clipping. Millions of people whose experience suggests otherwise are being fooled by their eyes or by level changes. I am not so sure.

I am sure. If they were not being fooled, they would be able to hear the difference under blind conditions. But they can't.

 

[rwortman]

I am sure. If they were not being fooled, they would be able to hear the difference under blind conditions. But they can't.

As I said before, many people have experienced gradually disliking the sound of something after having had it for months. As far as I know, no one has done this blind test: I listen to an amplifier for months. For some reason the music has a sort of edginess that isn’t as relaxing as I remember. I change it out for a new one. For several months all seems ok. Someone sneaks into my house and puts the old one back in, only inside the same case as my new one so I don’t notice.

The fact that some people couldn’t reliably hear a difference between certain amps, driving certain speakers, under certain conditions, does not prove that no one can hear the difference between any amps driving any speakers, under any conditions. It only means that under specific controlled conditions it’s hard to tell amplifiers apart.

 

[fpitas]

FWIW, a friend has Hypex UcD amps in his active system, including for his horns. I have noticed no listening fatigue after many hours.

 

[MarkS]

The fact that some people couldn’t reliably hear a difference between certain amps, driving certain speakers, under certain conditions, does not prove that no one can hear the difference between any amps driving any speakers, under any conditions. It only means that under specific controlled conditions it’s hard to tell amplifiers apart.

Sure, this is absolutely true. But there are plenty of anecdotes of people who THOUGHT they were listening to X, and hearing how much better things sounded with X, and then discovering that X was not actually in the system (usually due to some switch setting somewhere).

Also, I can believe that it can take a long time to first notice a particular flaw in the sound. But, once heard, it should be easier to tell whether or not that flaw is present going forward. IMO, it should not take another six months (or whatever) to be able to hear it again.

Also, it just makes logical sense that rapid switching should make it easier, not harder, to hear differences.

 

[rwortman]

Also, it just makes logical sense that rapid switching should make it easier, not harder, to hear differences.

I’m not sure. Perhaps it depends on the nature of the difference. I’m not sure of the magnitude of the change but as I said before, I think some audiophile writers who say the fact that we know we are being tested changes the way we listen and that may make it harder to hear subtle differences, might be correct.

 

[MarkS]

Fine, then let's just have those audiophile writers identify which component is in their system, A or B, when they don't know which it is, after listening as long they like (and after having declared that A and B sound different).

Of course, none of them can do this, except with (1) speakers and (2) poorly-measuring electronics.

 

[rwortman]

Of course, none of them can do this, except with (1) speakers and (2) poorly-measuring electronics.

This is an unproven statement.

 

[MarkS]

LOL! Go ahead and try blind listening yourself if you don't believe it.

 

[rwortman]

LOL! Go ahead and try blind listening yourself if you don't believe it.

As I have previously discussed, long term listening blind ABX tests when the subject doesn’t know they are being tested are almost impossible to administer. I am not going to purchase an old amp back, try to fit it into case identical to my current amp, and try to construct such a test. If I tell someone I want them to sneak into my house to swap out my amps, they might get shot.

I said this, “I think some audiophile writers who say the fact that we know we are being tested changes the way we listen and that may make it harder to hear subtle differences, might be correct.”

You said, ”Fine, then let's just have those audiophile writers identify which component is in their system, A or B, when they don't know which it is, after listening as long they like (and after having declared that A and B sound different).”

That’s not the same as listening without knowing we are being tested. I said they might be right about how tests change the way we listen, and you say make the test as long as you want. It’s still a test. Length is not the issue.

 

[MarkS]

So your claim is that a reviewer can tell if an amp sounds good if and only if he knows which one it is (and presumably how much it costs).

If he has to review it without knowing, that's so stressful that he can no longer tell if it's good or not.

Okey dokey. You pays yer money and you takes yer choice!

 

[Holmz]

... I also predicted your assertions would run into resistance, which they have.
…

It’s more complex than that.
Z

 

[rwortman]

So your claim is that a reviewer can tell if an amp sounds good if and only if he knows which one it is (and presumably how much it costs).

If he has to review it without knowing, that's so stressful that he can no longer tell if it's good or not.

Okey dokey. You pays yer money and you takes yer choice!

No, that’s not what I said at all. If you insist on mischaracterizing my argument so you can keep repeating the counter argument to something else, there is no point continuing.

I will state the proposition again. That when we know we are being tested, we change the way we listen. We listen differently when we are relaxed at home, listening for pleasure than when we do when we are under test, straining to discern differences. This seems plausible to me. This doesn’t mean we can’t hear any differences in the first case and have magical hearing in the second case. It just proposes that our ability to discern might be different. This has not been conclusively proven or disproven, to my knowledge.

We know that sighted listening changes our perceptions. That doesn’t mean we can’t hear a broken amp channel if the amp looks expensive. It affects us in subtle and unpredictable ways. It is not ”science” to conclude that this is the only condition that can effect our perceptions.

If we are going to tout our scientific credentials, we ought to have some idea of what it is to prove something. When a group of people, under blind ABX conditions, can’t discern between 4 amplifiers driving a set of speakers, that’s what it proves. That those amps, driving those speakers, under those conditions could not be identified. You might induce from this test that blind ABX testing will fail to identify any amp driving any speaker, but that’s a bit of a stretch. To induce that the amps are unidentifiable under any test conditions is not justified. We use blind testing to eliminate sight bias, not because we know our hearing is best when we are doing a blind test.

 

[Chrispy]

I have a Anthem MCA 225 gen1 amplifier that has a SNR of 120, 300 damping factor and Thd .0010%. the Anthem specs are past the audiable .Looking at the Amplifier rating chart I see the new Purifi D class amps have made significant improvement to the point that they surpass leading brands and go toe toe with the Benchmark. These improvements are way past audiable. And there lies the question, if it's past audiable are you actually getting improvement in the sound by going even further past the audiable range or are you simply wasting money. Is there an improvement in the frequency response or has this been put thru a blind test. I would appreciate anyone's experience in this.

Didn't read but this post. Don't worry about your amp unless it does have an audible issue you're trying to take care of, or you simply want more flexibility from the amp in terms of power or impedance handling etc....if it's not audible how would you even realize any "improvement"? You just have a case of upgraditis perhaps.....

 

[ahofer]

Science is the search for new knowledge

…pursued in a controlled, replicable fashion. Or it isn’t science.

And there really isn’t *any* proving. Only rejecting a hypothesis.

What you seem to be doing is rationalizing how something might be possible. That is a lot less compelling than the repeated rejection of audible differences under controlled testing.

Catalogue of blind tests

I thought this thread on Head-Fi was a valiant effort to put together blind tests that have been performed over the years. Given that there have been many more (I'm thinking Archimago's tests, among others), it would be fun to open source a complete list...

audiosciencereview.com