Can You Trust Your Ears? By Tom Nousaine

[Fitzcaraldo215]

The only differences in sound quality between low distortion solid state amps is when one particular amp cannot properly drive the loudspeaker in question.
Try comparing, unsighted two amps with similar specification into the same loudspeakers.
Keith

Keith - I do not have a major problem with your view. In case there is any confusion, I believe it is not inconsistent with anything I have said.

 

[Jakob1863]

So which society (secret) do I have to join? Are there member's dues? Will I be shown the secret handshake? So far you have offered a long winded version of , "I don't agree" without offering any details of your methods, how tests were done, why you my list of specs will not eliminate sonic differences. To have good results you would need to have tested amps with speaker loads that meet my described performance envelope, and yet were able to show in a reasonable manner they sound different.

We do agree manufacturer specs are often not comprehensive or done in standard ways. That isn't the same as saying the properly done tests aren't useful.

I wouldn´t call it "longwinded" , given the length of my post.
And of course, you correctly noticed that i´d up to now did not post more details about our tests. Not that you had offered any details about yours, have you?
But anyway, i hope we can agree that i´ve to invest my time to post it and that you could show some patience instead of posting this sort of grumbling.

PS. It was a matter of interest, i was searching for some additional informations about the swedish tests and thought what i´d find could be interesting for other members and then came across some posts i´d like to answer, not anticipating that it might bother "his highness"

 

[Purité Audio]

Fitz I could be wrong of course, but Ike when listeners hear a difference it is because one of the amps is incapable of driving the speakers or if the amps designer has deliberately designed it to be different , Dartzeel for example with their high ( for SS ) output impedance.
Keith

 

[Thomas savage]

There's some passive aggressive, snide undertones running through some of these posts of late. I'd be grateful for this not to escalate further and be very happy to see it dissipate some what.

Cheers

 

[DonH56]

Bad vibes?

Here is a link to the amp test "cube" I was referencing: http://audiograph.se/ AP also has articles about it on their site (can be linked to the AP analyzer).

 

[Thomas savage]

Negative waves

 

[Cosmik]

The "requirements of hi fi" aren't universally and rigorously defined, as far as I am aware. So, you have not proven your point.

The only point I have is that the purpose of an amplifier is exceedingly simple. There may not be a universal definition of "hi fi", but it's only a question of degree. Surely the general principle of the output tracking the input with zero (as close as we can get) deviation is clear.

How about this? The deviation, when listened to in isolation, should be below the threshold of human hearing in the typical dedicated listening room. Or something like that? If that was the case, not only would the error be 'silent' but it would be masked by the signal too, giving us a very generous margin against doubt.

 

[Cosmik]

There's some passive aggressive, snide undertones running through some of these posts of late. I'd be grateful for this not to escalate further and be very happy to see it dissipate some what.

What are you on about? I haven't noticed anything..? Or maybe it's me? I'm just trying to doggedly pin down what it is that audiophiles think an amp should do. One day I will succeed...

 

[Phelonious Ponk]

What are you on about? I haven't noticed anything..? Or maybe it's me? I'm just trying to doggedly pin down what it is that audiophiles think an amp should do. One day I will succeed...

Good luck with that.

 

[oivavoi]

What are you on about? I haven't noticed anything..? Or maybe it's me? I'm just trying to doggedly pin down what it is that audiophiles think an amp should do. One day I will succeed...

I think Thomas might have referred to the exchange between Blumlein88 and Jakob1863, not to your posts, Cosmik.

I also want a number after my nick, btw! Regards, Oivavoi67793,0003

 

[fas42]

What are you on about? I haven't noticed anything..? Or maybe it's me? I'm just trying to doggedly pin down what it is that audiophiles think an amp should do. One day I will succeed...

Easy to know when you hear one - the term usually applied is "effortless", meaning, that as the volume is altered nothing varies, except the intensity of the sound - it gives the subjective impression that one can raise the SPLs to any level one wants, without starting to have to cringe on "awkward" bits.

Of course, the world of motor cars is the same - a vehicle that one can accelerate to any sane speed, and then maintain that speed with complete composure and sense of control for the driver, in all situations.

 

[Sal1950]

The only differences in sound quality between low distortion solid state amps is when one particular amp cannot properly drive the loudspeaker in question.

I Agree and also that good SS amp designs have been totally transparent for 30 some years, IF
Why is it the some speaker designers are putting out products that they know (or damn well should), that the load they present will cause issues with many "good " amps? I've seen instances from FR variations to outright instability that just shouldn't be happening.
Are these instances of design voicing?
Is there some insider conspiracy to load the deck over who's amps might work (or not work) with speaker X? That could have reasoning from one friend supporting the other. Or a "good for commerce" platform where speaker X is so difficult a load that only the 200 lb $20,000 monoblocks can hang tight to some crazy crossover design (Big Money requires Big Money)?

I may be paranoid, but that doesn't mean there is no one following me.

 

[tomelex]

Cosmik,

Its a good question, the issue is a lack of standards in testing that exercise amps fully, some reasons two solid state amps measuring the same thd and noise at say 100 watts into a resistor, could sound different and not caught on your "typical and easy and safe audio tests".

the input impedance is not the same, so the output FR will not be the same
the output impedance is not the same, so the output FR will not be the same
the noise does not vary the same with output level
one amp has more or less feedback than the other, one sounds thinner than the other
the actual power reserves of one are barely able to meet the power output, the other one has several db of headroom for transients
the group delay between the two amps is different
the harmonic spray is different, audible differences in sound
one amp feedback network does not handle a fast transient without creating more harmonics
one clips different than the other, one soft, one hard
channel separation is quite different across the band
thd and imd is quite different across the audio band
damping factor is quite different between them
slew rate is different between them
one amp can meet full power with both channels driven, the other only when one channel is driven
the ability to handle reactive loads is different
crossover distortion at low levels is different, here is where the benchmark power amp shines way above a lot of much more expensive amplifiers
total bandwidth is different
amps distortions vary differently with power and load
one amplifier is 20 or 50 times the price of the other, so it always sounds better on sighted tests ahahahhah

 

[fas42]

...

While taking a break from the latest terrorism analysis and opinions, prior to going back to some non-political and non-vocal music, I was fooling around making little high frequency hiss noises with my mouth, stretching to create ever higher bands of hiss (as measured on an RTA), and wondering why I could (at least seem to) hear hiss that only excited frequencies above what I can hear as a tone...

And suddenly my eye again fell upon the MiniDSP plugin and this time I noticed that I'd left a slight delay on the right side from some prior mucking around.

I eliminated the delay, and my antique system returned to what passes as perfection here.

Even though I don't trust my ears, they do a pretty good job at times trying to tell me something isn't good here.

Missed this piece by Ray earlier ... excellent example of how to go about resolving system issues: your ears are not telling you whether something is better than something else - it's all about, whether "something sounds wrong". This is precisely how I go about troubleshooting - I know what it should sound like; if it doesn't, then there is an issue somewhere ...

 

[krabapple]

If you get to a point that a difference is not detectable at elevated levels and small excerpts, it tells you the difference will be undetectable under sighted conditions and at equal or lower levels or with longer auditioning.

Conversely, if 'training' via a raised-level audition of a fleeting 'tell' is the only way you can ace the ABX, it indicates you probably do not really hear a difference at all under normal , 'pre-trained' listening conditions, much less a difference even remotely approaching the 'night and day, veils were lifted, the sound just bloomed, even my wife could hear it' etc nonsense that audiophiles (and hi end reviewers) routinely report.

 

[krabapple]

Really, I love sighted testing to work as it is so much easier to do. But it just doesn't.

Yup. Perceptual bias controls are a bedrock of sensory science. Required by every peer-reviewed journal I know of. Your statement is utterly uncontroversial.....

....except in audio forums.

It's interesting to see you here, Amir, making the same reasoned arguments (e.g., we don't operate from a base of no knowledge, not all possibilities are equally likely, etc) against the same old (sometimes repurposed in faddish new 'sciencey' language) zombie arguments that desperate audiophiles have been hurling against science for decades now.

There are people, here too, who will *never* accept the truth.

 

[krabapple]

This is a very narrow definition of qualitative approaches. I do qualitative social science work, and I identify very strongly with a neo-positivist tradition. Jakob1863 is right: qualitative research is often about exploring what people think and experience, in more depth than quantitative research is able to do. This doesn't need to entail a relativist view of truth.

People can 'think' and 'experience' that a DUT (device under test), presented twice, is two different DUTs. That's an interesting phenomenon to study. But it doesn't mean that there were really two DUTs.

 

[krabapple]

If we can't trust our ears, which ears are we going to trust?

How about just accepting that you might be wrong?

 

[krabapple]

In actual fact, no one wants it to be true that any type of amplifier or DAC is 'more than good enough'.

Wrong. As someone who's been listening to music through gear for 40something years, I'm happy when such level of performance has reached commodity status. I want that to be true for all the gear in the chain.

 

[Jakob1863]

People can 'think' and 'experience' that a DUT (device under test), presented twice, is two different DUTs. That's an interesting phenomenon to study. But it doesn't mean that there were really two DUTs.

Which is imo a strange reaction to oivavoi´s post.
Maybe it would help to read something about qualitative methods and why it is often used in scientific work; sometimes a combination of quantitative and qualitative methods gains really astonishing results.....