Can you hear a difference in Sound between Audio Amplifiers?

[Goliath]

Memory does fade over time, and you (if you are a human) cannot reliably remember very subtle differences in sound over long periods of time.

I'm inclined to agree, but people often claim it's a second, or it's a few seconds, or a little more etc. I don't know enough about this stuff, so it's all very confusing. Some people say it's less than a second. If there is some reading material or research done that points to a certain number it would be informative.

 

[Irvrobinson]

Imagine if the stress excuse were used by a pharmaceutical company when trying to prove that a drug really works. It is just as laughable and stupid with audio.

That's not a good analogy. Drug testers are generally not being asked to make a conscious choice based on perception. Have you ever participated in one of these audio comparison tests? Especially a DBT?

 

[Goliath]

I'm confused now. So is stress a variable that could affect our ability to discern subtle details in a controlled test??? Or is it just one giant excuse. I'm all ears.

 

[Pyrrho]

I'm inclined to agree, but people often claim it's a second, or it's a few seconds, or a little more etc. I don't know enough about this stuff, so it's all very confusing. Some people say it's less than a second. If there is some reading material or research done that points to a certain number it would be informative.

I don't have any links off the top of my head for that. Maybe mtrycrafts will see this and reply, as he has been a great source of links to things of a like nature in the past.

 

[Pyrrho]

I'm confused now. So is stress a variable that could affect our ability to discern subtle details in a controlled test??? Or is it just one giant excuse. I'm all ears.

It is mostly an excuse. See jinjuku's earlier remarks:

For starters we aren't pushing DBT. Just SBT. Secondly at both AVS forum and Polk Audio Forums in cable 'burn-in' threads I offered $100 to charity and two sets of randomly labeled cables, two burned in and two never used, the tester would have 30 days.

So this removes:
1. Any blind testing. All testing would be sighted
2. Low stress as the participant would have plenty of time and no test administrator present
3. It would be in their own listening environment and their own equipment (also very stress reducing)

Guess how many takers?

I actually don't elaborate on that type of stuff. You simply get into the territory of subjective vs the objective. I let that cable challenge, and I consider it very friendly and accommodating, speak for itself.

It's a very neat and tidy box that they can't crawl out of:

AVS Thread

Polk Thread

See for yourself. It's pure gold . So much so that Bob Lee, Lead Applications Engineer at QSC and Secretary of Audio Engineering Society (AES) had this to say:

"Good god, those threads are hilarious! Reading through them is like watching Copernicus wander through a conference of astrologers."

Basically, people who have weeks to do a test, in their own home, without anyone else present, are unwilling to do it. This is because they are full of ....

People can claim any ability they want. But if they do not show that they can really do it, and if no other human has ever shown the ability to do it, then only an idiot is going to just believe all the crap that is claimed.

 

[Grador]

Stress is often used as an excuse, but I think there can be little doubt that it is a real factor in perception.

 

[Pyrrho]

We all know speakers and room make the big difference. Not subtle and slight, but big. As far as electronics goes, it is the processors that make the big difference.

Subtle and slight differences are not that important, are they? I mean subtle and slight?

So what if amps make a subtle and slight difference?

If you hook a pure class A analog preamp (no processing whatsoever) to any power-equivalent amps, the difference will be no more than "subtle and slight".

You know, this is something that should be stressed. People spend crazy amounts of money on things that are so "subtle" that they do not show up in blind testing, instead of spending that same amount of money on things that make such a big (and actually real) difference that they do show up in blind testing. This means, EVEN IF THEY WERE RIGHT THAT IT MADE A DIFFERENCE, they are still idiots.

 

[Irvrobinson]

You know, this is something that should be stressed. People spend crazy amounts of money on things that are so "subtle" that they do not show up in blind testing, instead of spending that same amount of money on things that make such a big (and actually real) difference that they do show up in blind testing. This means, EVEN IF THEY WERE RIGHT THAT IT MADE A DIFFERENCE, they are still idiots.

Well, that's taking this discussion to a new, and IMO an unwelcome level. How about turning down the emotion level a bit?

Just because an effect is subtle, and is difficult to identify in a test procedure, does not mean someone making a purchase decision on that criteria is an idiot. I'll ask again, have you participated in an audio SBT or DBT?

 

[Grador]

Well, that's taking this discussion to a new, and IMO an unwelcome level. How about turning down the emotion level a bit?

Just because an effect is subtle, and is difficult to identify in a test procedure, does not mean someone making a purchase decision on that criteria is an idiot. I'll ask again, have you participated in an audio SBT or DBT?

Agreed. Also what if I really like the sound of my setup but would like to improve it a touch? Changing out my speakers or treating my room could make dramatic changes to the overall sound character that I do not want.

 

[Goliath]

Stress is often used as an excuse, but I think there can be little doubt that it is a real factor in perception.

So stress can be used as an excuse but it can also be a valid excuse since it can affect our ability to hear? Am I understanding you correctly?

 

[Grador]

So stress can be used as an excuse but it can also be a valid excuse since it can affect our ability to hear? Am I understanding you correctly?

Yeah that's basically what I'm saying. I would say that most people use stress as a "this doesn't agree with what I think, so it must have been stress" excuse rather than a valid point of contention though.

 

[mtrycrafts]

Agreed. Also what if I really like the sound of my setup but would like to improve it a touch? Changing out my speakers or treating my room could make dramatic changes to the overall sound character that I do not want.

But that is relative. You'd have to change it enough to be audibly different, no? How will you know if this is happening? How do you know when it is imagined or when it is real? No end to chasing imagined differences, no?

 

[cornelius]

Thanks jinjuku. I imagine no takers. : ) Can you elaborate on auditory memory of subtle details? What I hear regularly is that people say they hear audible differences more easily once they get used to the equipment. The differences are more pronounced over time. But I also hear that audible differences are more easily noticed if the switching is done rapidly. It is a little confusing.

Is their truth in the matter of how poor human auditory memory is and if so, is there any reading material you recommend I gloss over that may shed light on this?

For the record, I used to hear lots of differences between amplifiers, and I've owned a few... But a couple of years ago when I was looking for a pair of monitors, my view on this changed when I bought a pair of Harbeths. Alan Shaw, the owner/head designer of Harbeth, has a user group forum, where I was able to get lots of great info. But what surprised me, was his stance on cables and amplifiers - he doesn't recommend esoteric gear/accessories. I was surprised because his speakers are expensive, usually when I see expensive speakers, expensive cables and amplifiers are hooked up to them (and endorsed by the speaker company).

He makes a great effort on his site to give good examples as to why amplifiers and cables sound the same (unless they're doing something wrong). Below is a thread that may answer a few questions on how our senses work. It's a long thread (sorry), but Alan comes up with some great little tests (both visual, and audible) that will shed some light. Take the time to go through it - you can probably just focus mostly on his posts, to save some time...

Working with the human ear: the proper evaluation of audio equipment incl. amplifiers

 

[mtrycrafts]

If an experimenter does not adequately train the listeners or test subjects prior to the actual test, then hearing sensitivity would be somewhat reduced in terms of detecting audible differences between gear. Surely? How do we know all SBT or DBT's employ strenuous training? Perhaps they don't. Perhaps most don't - it's all speculative, but you would imagine they would.

You can be sure that research facilities use traind people.
I can ask how many golden ears have that level of training to detect differences? Probably very close to 0. How many mag reviewers have that certification from a recognized training facility???

 

[mtrycrafts]

I don't have any links off the top of my head for that. Maybe mtrycrafts will see this and reply, as he has been a great source of links to things of a like nature in the past.

Did I see my name with a request?
While I don't have an actual credible journal article on this, I have a letter response from a Thomas J Smurthwaite, Ph.D., licensed Psychologist about just this in Audio, Jun 1999, page 6.
He stated about 2 seconds. "After this time echoic memory either decays or is processed into immediate memory, which imposes significant limits on the amount on the amount of information that is retained."
I would think that for better data you need to scour the psychology journals for echoic memory and immediate memory and longevity of each? The author went on for several paragraphs.
Perhaps a local library's interlibrary request or Internet search for that page could bear fruit

 

[mtrycrafts]

Yeah that's basically what I'm saying. I would say that most people use stress as a "this doesn't agree with what I think, so it must have been stress" excuse rather than a valid point of contention though.

Well, when you cannot perform....

 

[Grador]

But that is relative. You'd have to change it enough to be audibly different, no? How will you know if this is happening? How do you know when it is imagined or when it is real? No end to chasing imagined differences, no?

Well that's a question of how subtle. I would also say that it doesn't really matter if the difference is imaginary as long as the person is happy in the end.

I agree that almost everything that makes a "subtle difference" actually does nothing and you won't see me buying any expensive cables and ceramic isolaters to keep them off the floor, but to call someone an idiot for seeking subtle improvement over large change I cannot agree with.

 

[Pyrrho]

Well that's a question of how subtle. I would also say that it doesn't really matter if the difference is imaginary as long as the person is happy in the end. [emphasis added]

I agree that almost everything that makes a "subtle difference" actually does nothing and you won't see me buying any expensive cables and ceramic isolaters to keep them off the floor, but to call someone an idiot for seeking subtle improvement over large change I cannot agree with.

But it does matter. If the person persuades others of the falsehood, then they, too, may waste their money. This also means that con artists are likely to be rewarded as well. Rewarding con artists encourages more people to become con artists, and so the damage spreads, like a disease on humanity.

Basically, you are saying that the truth does not matter, and it is fine for people to believe falsehoods and to spread their falsehoods to others. Do you really think that is okay and harmless? Don't you think that people who are careless about one issue are more likely to be careless about other issues as well? After all, if scientific testing is unimportant for determining facts related to audio, why would it be relevant to anything else?

 

[Irvrobinson]

For the record, I used to hear lots of differences between amplifiers, and I've owned a few... But a couple of years ago when I was looking for a pair of monitors, my view on this changed when I bought a pair of Harbeths. Alan Shaw, the owner/head designer of Harbeth, has a user group forum, where I was able to get lots of great info. But what surprised me, was his stance on cables and amplifiers - he doesn't recommend esoteric gear/accessories. I was surprised because his speakers are expensive, usually when I see expensive speakers, expensive cables and amplifiers are hooked up to them (and endorsed by the speaker company).

He makes a great effort on his site to give good examples as to why amplifiers and cables sound the same (unless they're doing something wrong). Below is a thread that may answer a few questions on how our senses work. It's a long thread (sorry), but Alan comes up with some great little tests (both visual, and audible) that will shed some light. Take the time to go through it - you can probably just focus mostly on his posts, to save some time...

Working with the human ear: the proper evaluation of audio equipment incl. amplifiers

Right. Harbeth is so focused on the objective, and then they point you to product reviews from The Absolute Sound and others that are completely subjective, and don't bother to mention the Stereophile review where the 40.1 produced some rather controversial measured results. Someone so out-spoken might consider walking the walk.

I like the part about offering up a pair of 40.1s as a prize. Right, just put together a test that reveals results no one has ever been able to demonstrate, and I'll give you a big prize. Where have I heard this before?

Anyone who has ever sat through rigorous comparative audio testing in SBT or DBT conditions knows these tests never reveal anything but obvious differences. Everyone knows. If you haven't tried blinded testing you need to try it. The process is usable for speakers, I've been in those too, but for amplifiers? I don't see how. There are only two responses in blinded testing: 1) Ah ha!, and 2) WTF did I just hear?

 

[RichB]

It does matter if as the average person want to select the proper amp that fits within their budget.
And, of course no one should buy an aftermarket power cable unless theirs is too short or they don't like the color

- Rich

P.S. Anyone know where I can find white power cables?