Blind Listening Tests & Amplifiers

[UncleJessie]

In response to:

To those who belive so solidly in blind testing, I say that the entire test setup and methodology needs to be examined very closely, and this very much includes the skill levels of the listeners.

ITU BS1116-1 addresses these issues. The standard calls for a double blind triple reference with hidden stimulus test. The test subjects must qualify as expert listeners to participate in the test. This is all explained in the ITU document which can be downloaded for free from the ITU website.

-UncleJessie

[Steve Eddy]

Originally posted by grataku
Since you seem to be into it why don't you try this test: with a bunch of people, play something on one system, then change a component and record differences between the two systems on a piece of paper. Compare notes at the end. I bet you'll find that most everyone will have heard the same difference in sound.
Report back, please.

Try a similar test. Tell them all you've changed components but don't actually change anything. Report back, please.

se

[grataku]

Originally posted by Steve Eddy


Try a similar test. Tell them all you've changed components but don't actually change anything. Report back, please.

se

My test didn't involve a blind state so what you are proposing is radically different. You could empty out an ML case and stick one of Peter's gainclones in it to see what role a big enclosure plays in the listener's mind.

[moe29]

i just happened to be reading the A75 article on PassDiy web site
and thought Mr. Pass' comments applied to what is being
discussed in this thread.

The right brain/left brain theory applies here. You use one side
of your brain for objective logical kinds of processing, and the
other for subjective and emotional. When you are enjoying music,
the subjective half is in play, and its process does not relate to
the specs very well.

The same phenomenon explains why A/B comparisons, no matter
how well staged, do not resolve what audiophiles claim to hear.
When you are sitting there trying to hear the differences
between products, the objective side of your brain begins
working and your subjective responses get locked out by the
pressure to make an objective decision.

I think i notice differences in components after i've lived with them
for a while. I just put a new pre-amp in my system, and over the
last few days of listening i've noticed myself becoming more
involved with the music - it just feels better - as well as sounds
better. just my 2 cents worth.


m.

[Peter Daniel]

When listening to recorded music I don't try to remember sonic signature of a given equipment or setup, because when differences are small it may become mind boggling indeed. I'd rather prefer to relax and identify my own reaction to the sound I hear. When something is not right, it's usually very obvious, because I can't concentrate on music and sounds exist beside me, without any emotional content on my side. When everything is right, or when the change I just did was significant the music grabs me and gets me involved (at least for awhile) and I'm eager to try another recording to see how it's different this time.
I'm sure many of you went through that and my question is, how this happens, when seemingly in DBRCT you cannot identify the subject consistantly?

I guess I got my answer in previous post

[nw_avphile]

Some really good feedback here! Overall, there appears to be more of you who support blind testing (on some level) than those who do not.

Someone else on another forum said something like: "If buying a $1000 rock and setting it on my amplifier makes it sound $1000 better to my ears, it was $1000 well spent." I can't argue with that logic. Some people buy a performance or luxury car not for the performance or the luxury but because it makes them feel good to own/drive it.

One of you said:

"But I have always been amused at how 'night and day' differences tend to simply vanish once the listener is simply denied the knowledge of which component they're listening to."

The above really sums up my experiences in one sentence. The following is a very good example:

I recorded a friend's audiophile "reference" vinyl album (the one he most often uses for equipment evaluation) onto CD-R when CD-R was still a relatively new thing for audio. I used a studio-grade sound card, my above average turntable/arm/cartridge, and a high quality phono preamp of my own design. I then started the real vinyl playing on his system AND the CD-R playing in his CD player and invited him in to allegedly listen to some new cables I'd brought over and wanted his golden eared opinion on.

This person LOVES vinyl and, pretty much hated CDs. He despised all things digital and had a stellar system with a tricked out Linn LP12 and Ayre electronics driving B&W 604s. He sat down to listen to the new cables and said they were very similar to his own, but he picked out some minor differences. When I revealed he was listening to a CD recording of his vinyl, he didn't believe me. He got up and looked at the input selector on the Ayre preamp and suddenly was angry and defensive!

In reality, he was not only listening to his much hated CD format, but a computer soundcard ADC, a different turntable, different tonearm, different cartridge and different phono section! Now, in fairness, this wasn't a back-to-back test. It had been a few weeks since he'd even listened to that album, but the results were stunning. He not only enjoyed listening to a CD, but one recorded on a computer on someone else's set-up! This was a guy who would spend all day aligning his cartridge and raising and lowering the tonearm until he got the sound just right.

We later did an A/B blind test with the CD vinyl recording level matched to the vinyl. We both passed the blind test with flying colors. The real vinyl sounded plainly better than the CD-R.

But the point of this story, is to show the power of the human mind. When he THOUGHT he was listening to his carefully tweaked turntable, the stunning Ayre phono section, etc. that's exactly what he heard. He only heard tiny differences he attributed to the interconnects I'd brought over. All the familiar ticks and pops were there. He had no reason to believe he was NOT listening to his turntable so he heard what he expected to hear.

Vinyl lovers (including the one above) claim that CDs hurt their ears and have all sorts of gross offensive sonic flaws. They would certainly claim to know one when they heard it. It's not too different than someone who claims they could easily pick out a few hundred dollar mainstream receiver or integrated amp from a quality power amp. It turns out, it's not so easy!

As for "all amps sound the same", I'm not saying that by any means. As I said in my original post, some measure different, and hence sound different. They also differ widely in their power and current (low impedance) capabilities.

Those of you who argue even if they measure the same, they don't perform the same driving real speakers with real music, I suggest you investigate null tests where you can objectively and subjectively evaluate an amplifiers performance doing just that.

By listening to the difference signal, you can get a feel for what sort of distortions the amplifier is producing and by measuring its amplitude and spectral content, you can have a good objective indicator of how it's altering the signal under real-world conditions.

[Peter Daniel]

Originally posted by nw_avphile


As for "all amps sound the same", I'm not saying that by any means. As I said in my original post, some measure different, and hence sound different. They also differ widely in their power and current (low impedance) capabilities.

Those of you who argue even if they measure the same, they don't perform the same driving real speakers with real music, I suggest you investigate null tests where you can objectively and subjectively evaluate an amplifiers performance doing just that.

By listening to the difference signal, you can get a feel for what sort of distortions the amplifier is producing and by measuring its amplitude and spectral content, you can have a good objective indicator of how it's altering the signal under real-world conditions.

What about the claim that changing passive parts inside the amp changes its sound? It still measures exactly the same (providing same values are used) yet, to some, it sounds totally different. Is there any truth to that?

[Steve Eddy]

Originally posted by moe29
i just happened to be reading the A75 article on PassDiy web site
and thought Mr. Pass' comments applied to what is being
discussed in this thread.

The right brain/left brain theory applies here. You use one side
of your brain for objective logical kinds of processing, and the
other for subjective and emotional. When you are enjoying music,
the subjective half is in play, and its process does not relate to
the specs very well.

The same phenomenon explains why A/B comparisons, no matter
how well staged, do not resolve what audiophiles claim to hear.
When you are sitting there trying to hear the differences
between products, the objective side of your brain begins
working and your subjective responses get locked out by the
pressure to make an objective decision.

With all due respect to Mr. Pass, this makes no sense seeing that virtually everyone who tries out a new component, or cable, or tweak, or mod or whatever is engaging in an A/B comparison and audiophiles routinely sit down and try to hear differences and almost invariably they purport that they do hear differences. So this objective side of the brain certainly doesn't seem to be getting in anyone's way.

se

[Peter Daniel]

On few occasions I've heard no difference at all.

[Steve Eddy]

Originally posted by Peter Daniel
What about the claim that changing passive parts inside the amp changes its sound? It still measures exactly the same (providing same values are used) yet, to some, it sounds totally different. Is there any truth to that?

Well, until you can confidently remove the psychological element, one can't really say with any degree of certainty.

se