Blind Listening Tests & Amplifiers

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diyAudio Senior Member
Joined 2002
TONED DOWN...

Hi,

I do'nt think the idea here is that you take everything you are told at face value, or indeed that you have to believe everything in every article, book, or paper.......the idea is to pick out the wheat and discard the chaff....and not to throw the baby out with the bath water...

Now, that's an idea even I can live with.;)

And to add insult to injury: I find the concept of wheat and chaff sorting quite healthy.
It takes both knowledge and experience to weed out the garden I'd say.

Cheers,;)
 
Disabled Account
Joined 2002
...to continue pan,

...No...i don't think anyone is saying everything sounds the same'......

....transducers certainly need time to bed in.........indeed the characteristics of 'speakers change with tempreture, humidity, etc......

...forget loudspeaker cables though, so-called 'high-end', multi-thousand dollar wires constitute one of the greatest frauds ever perpetrated on the gullible...period.

....and....all audio power amps. do sound the same given the conditions i painstakingly detailed earlier in this thread.....period.

nothing personal, plenty of hard unassailable scientific evidence...period.
 
Detection and imagination

I think we have gone way too far past each other in this discussion.
It is clear to me that most subjectivists will kep believing whatever they are used to believe and use straw man methodology to discredit true objective tests.
Fine.

Lets just make one last thing clear here.

In order to detect differences between say two amps subjectivists will use their ears, I presume. Sixth sense might get involved but so far noone took it that far.
In order to hear something, eardrum must get excited. For that we need difference in pressure level (sound). This sound is produced by speaker, which no surprise requires some current in order to move (regardless of principle - dynamic, electrostatic, plasma, ribbon, piezo, you name it).
So let's agree here :
No electric signal (current flow), no sound. Nothing to detect (hear).

This is our Principle. With me so far ?

Now, the current is provided by amplifier. It can be shown that signal arriving to speaker terminals consists of two componnets : a perfect multiple of the input signal (this is what we want) and something else which we call distortion. This can be of harmonic nature, crossover (switching) residuals, intermodulation distortion, random noise, power supply residuals, cable induced distortions, RF pickup, parasitic oscillations, crap coming from the electric outlet finding the way through, you name it.
In order to HEAR the particular distortion (in order to reliably identify component in hand - the wholle amp, one resistor, cable, connector, whatever), this particular distortion has to be extracted by our ear/brain system from 1) useful signal and 2) all other distortions present.
By the way, component (2) will show easily if we substract the input signal (so called null test) in case of amplifier. But some even larger distorions will be also introduced by the speaker and the room.

One can argue till cows come home, but there HAVE been experiments conducted to establish what level is required for human ear to detect. This is pretty complex issue, as it depends on many variables (whether there is a correlation between signal and distortion) but bottom line is our ear is really NOT a very good detector. Its ability to detect sound is far, far inferior to our ability to measure electric signals. I mean FAR inferior. We can measure picovolts (1/1,000,000,000,000th of one Volt), and millivolts (1/1000th of a Volt) are dead easy. One millivolt at speaker terminal will not be detected by anyone's ear. That would be akin to plugging your Moving Coil cartridge directly to the speaker ! If you could hear that, you would save yourself great deal of money on expensive pre-pre, preamps and power amps too.

So question number one - how can one hear difference if we can't measure it ? (remember the Principle - no current, no sound ?)

Let's go further. Lets say that we CAN measure difference (and indeed we can, even in case of a single capactor or resistor changed, or a power cable swapped). In some case it will take quite ingenious setups to do this measurement, as differences will be minute. How much difference do we need to see before we can hear it ? It turns out, a lot.
In presence of loud sound (our "good" signal coming out of the speakers), ear's ability to hear tiny "bad" signal (distortion) diminishes greatly. Furthermone, it has pretty difficult task of telling THIS particular distortion from all the other ones. And those "other distortions" could, in say case of swapped power cable or say 3c resistor replaced by 75$ one, be more than MILLION TIMES larger than the distortion you're trying to hear. Can you really believe that you can hear THAT ?
I can't. No person who understands this can.

But feel free to disagree using whatever illogical argument you may invent now. I have nothing more to add really.

Bratislav
 
"It is clear to me that most subjectivists will kep believing whatever they are used to believe and use straw man methodology to discredit true objective tests."

I believe what I believe, I know what I know, some things in life I´m uncertain about, and I do very much believe in well excecuted objective tests, never said the contrary.

"This is our Principle. With me so far ?"

Yes, I think I had a clue about that there was someting flowing to the speakers in that cable thingy, what you call it.. .current, oh yes, thanks!

"But some even larger distorions will be also introduced by the speaker and the room. "

This is the reason I say that many tests have been excecuted in the wrong way, often using less than SOTA speakers and using non treated rooms. I DO NOT BELIEVE I WOULD HEAR THE DIFFERENCES I TALK ABOUT IN SUCH A TEST EITHER.

I therefore have spent most of my money on the room and speakers. About $8000 on acoustic tools and loudspeaker parts, and much less on the rest of the rig.

"you would save yourself great deal of money on expensive pre-pre, preamps and power amps too."

I don´t use a pre in my rig because it colours the sound, instead I use a impedance optimized passive solution. The power amps I build myself to save money. Money should be put on speakers and acoustics where they make the biggest difference.

"So question number one - how can one hear difference if we can't measure it ? (remember the Principle - no current, no sound ?)"

We can not hear a difference if there is no measurable difference, that is clear as a bell. I know some people beliewe in "magic" in hifi equipment, plaese do not put me in that camp.

"How much difference do we need to see before we can hear it ?"

I don´t have exact numbers, but I expect not a lot. Since a CDP with low THD+N improves dramatically after a clock mod and amps with less than 0.05% and flat fr. response sound different, not to mention cables.

"And those "other distortions" could, in say case of swapped power cable or say 3c resistor replaced by 75$ one, be more than MILLION TIMES larger than the distortion you're trying to hear. Can you really believe that you can hear THAT ?"

First of all I don´t think it´s so much a question about $, but to answer your question, yes I can easily hear difference between loudspeaker cables and caps to the Accuton tweeter I use.

"I can't. No person who understands this can."

I wish I could invite you to my home for a listening session, you would be surprised what You can hear in my audio room :)

Happy listening!

/Peter
 
Re: ...to continue pan,

mikek said:
...No...i don't think anyone is saying everything sounds the same'......

....transducers certainly need time to bed in.........indeed the characteristics of 'speakers change with tempreture, humidity, etc......

...forget loudspeaker cables though, so-called 'high-end', multi-thousand dollar wires constitute one of the greatest frauds ever perpetrated on the gullible...period.

....and....all audio power amps. do sound the same given the conditions i painstakingly detailed earlier in this thread.....period.

nothing personal, plenty of hard unassailable scientific evidence...period.

About the "everything sounds the same" issue, I think you know what I meant.

Cables, agree with you expensive cables are the biggest "fraud" and I would never pay more than $30-40 for a pair. However that does not mean that there is no audible difference. Turns out we are lucky since excellent DIY solutions can be made for peanuts :)
The best cable I have had in my system is two pieces of unrolled copper foil inductor without insulation at a cost of $15. Sounds better than Flatline red dawn and AQ $1700 "frauds" (that actually sounded good)

To repeat myself, if two amps have truly identic behaviour under all practicall situation as reactive loads and different levels, then off course there would be NO audible diference. Since there are no two amps that are identical, there will never be two amps measure exactly the same. Now can we hear that is the question we have been beating to death here :) and off course that depends on how much the measured difference is.
Listening tests indicates that we hear much smaller errors than some have been made to believe and/or our measurments fails to get the whole picture (so to speak) when an amp drives a complex reactive load with complex program material.

This amps I have tried I can tell apart in a couple of seconds, that big a difference there is.

Audio Research VT100
GamuT D200
Pass Aleph 5
Zapsolute
Patriot V100
Gainclone
Holfi Integra and Audis
Luxman
Arcam

Maybe these manufacturers lies about the THD levels and the reason I can hear the difference so easily is because off high distortion. I suspect not though, but simply that a high resolving rig can and do differentiate between such low distortion amps as above.

Happy listening :)

/Peter
 
Everything is different

Please let me clarify my position, and as an example I can tell you an experience I had just a few days ago.
I went to visit a friend of mine in an Hi-Fi distributor, with some cables I made on my hand.
I asked him if we could compare my cables to some comercial designs.
He told me he was out of stock, but could get two examples from Wireworld.
One costs around 80 Euros, the other is their top of the range, costs around 1000 Euros.
He connected my cables and the 80 Euros ones from a cd player with two fixed outputs to a preamp.
I was with an excellent disc on my hand, by the way, to test this things: Joe Jackson - Volume Four (his last CD).
While playing, I asked him what was the cable it was playing right now.
He told me "it doesn't matter".
It ended up like a blind test.
Final results were that I liked my cable over the 80 Euros one (the difference were night and day).
With the 1000 Euros one I could hear some subtle sound I wasn't aware in the beginning.
My friend had the same oppinion, and he knew all the time what was playing.
So, I don't consider "golden-ear" myself, but I think I can detect two different amps.
But the best one for me can be the worst for someone, who knows?
Would I go to the trouble to measure all these cables?
Of course not!
By the way, the cables I made are UTP Cat.5 network cable, with some cheap gold-plated plugs, silver soldered.

nw_avphile, I really think you must be a saint.
You really have the patience to repply to all these people (me included).
But it seams to me you haven't learned anything.
I still need to know what music do you hear when testing an amp.
Elevator music?:devily:
 
Some final thoughts and comments

It's strange, after more than 700 messages in this thread, people here (i.e. Pan, carlosfm, mrfeedback) are suddenly starting to post of blind or "semi-blind" listening tests they've been involved with. Why weren't the results of these tests brought up much earlier? So far, none of them have been very credible.

A lot of objective evidence has been presented in this thread that strongly goes against the beliefs of some people here. That information is apparently VERY threatening to some members here. Audio appears to be their primary hobby and some have admitted to having a lot invested in it. To have someone come along and tell them some of their efforts may not result in any real benefits is obviously threatening.

As mikek and others have indicated, some here are always going to believe what THEY WANT TO BELIEVE, regardless of any technical explanations, regardless of published studies, regardless of psychoacoustics, and regardless of what anyone here says. THAT'S FINE. I'm sure some people still believed the world was flat when science proved otherwise. But it's not fair to try and shoot the messenger and accuse them of being deaf, dumb, drunk, listening to elevator music, etc--especially when no objective information is presented to support their attack.

If the GoldenEars here want to attack something: Try countering, by OBJECTIVE means, the points made at these links:

http://www.dself.demon.co.uk/subjectv.htm

http://2eyespy.tripod.com/myaudioan...mepage/id5.html

If possible, provide references to support your counter arguments, just as the authors have at the links above.

Just to be clear, I'm NOT saying that everything sounds the same. Blind tests have been done, for example, where people can easily discern a tube amp from a solid state one. Some amps have audible distortion characteristics that are very real. If you're comparing two amplifiers, it only makes sense to use blind testing to identify any REAL differences and help you decide where to go from there.

I want to thank everyone for their contributions to this thread. I've learned a lot about human behavior, statistical analysis and how DIY folks approach the world of audio. My main hope, however, is that many others have learned something too.

I've seen some of you "come around" on your point of view and at least admit things like psychological bias is a real problem and amplifiers that measure sufficiently close should sound the same (i.e. the Carver Challenge). I hope for everyone who's posted to this thread, there are dozens more "lurkers" encouraged to try some blind listening to see what really makes a difference to them in their own systems. I also hope that some of them will post their results to this or other forums (even at the risk of being ridiculed by the GoldenEars like I have been).
 
nw_avphile,
I don't blame you for throwing in the towel, but how about the secondary reason you gave for opening this thread? Remember we were going to come up with ways for saving money?
Why don't we extend a challenge to the "golden ears" to comeup with a list of upgrades they have done, that made their component sound better, and were cheaper than what they replaced? Out of the thousands of more expensive upgrades they have made, you would think that at least a few could save us some money.
For example: "Gold wire is really great, but when I replaced the gold wire with silver wire it sounded so much more transparent."
 
Hold your horses

"Why weren't the results of these tests brought up much earlier? So far, none of them have been very credible."

I´ve told you what I can hear, isn´t my word enough for you?
It use to be for other people. Yes I´ve done some blind testing so what, they go hand in hand with what I´ve known to hear all the time (or for years anyway:))

Do you suggest that I made this up, that I lie to "protect" my opinions?
I hope not but that was the way I read your post, bad attitude in such case.

The first test I wrote about I can´t "proove" to you since that was done 7 years ago or so, when my hifi rig started to become transparent enough (but nowher close to SOTA) to show up difference between stuff.

I must ask you, do you seriously believe that a $100 discman, a $700 CDP and a $700 DAT would sound the same???

About the other test I wrote about, I still have the disc with the tracks, would you be interested in receiving a copy to hear the difference between some top quality microphone preamplifiers?
I sing and play like a junkie, but I have tons of fun... :)

"A lot of objective evidence has been presented in this thread that strongly goes against the beliefs of some people here"

This is soooo silly, please come home to me and hear for yourself, those people that present fact that goes against my "beliefs" are not worth much, because it is totally false since I can proove it wrong to any person on my rig.

"That information is apparently VERY threatening to some members here"

Not threatening to me for sure.

"Audio appears to be their primary hobby and some have admitted to having a lot invested in it"

It´s one of my biggest hobbys besides of making music, rockclimbing and workout/health/sports. Unfortunately it is the most expensive but for me it´s worth it because of the joy it gives me. Besides I´m not into bar hoping and have no children to support so the money I spend on hifi and music isn´t much more than many of my friends spend on cigarettes and bars/pubs.


"To have someone come along and tell them some of their efforts may not result in any real benefits is obviously threatening"

Not at all. 75% or so of my hifirig investment are on speakers and acoustic tools because this is what is most important for top notch sound. I can not believe that anyone does not think speakers and room acoustics makes a huuuge and dramatic difference. So I have really got improvements from my investments so far. The amps I´ve built myself and they did not cost much compared to the competition, The SACD was the cheapest I could find ($400 inc. 3 records :)) but I moded so it compares to SOTA players. Home made attenuator and cables. My speaker cables cost me a whole $15....

All changes I do (buy stuff) must result in an audible improvement.
I have had some of the better amps on the market at home. I had the money to buy them and could clearly hear the difference to my amps, but... my amps are as good as those other amps (see earlier post)so I still have them. Had I thought that one of the amps I tried was better (as a total) than my amps I would have bought it without hesitation.

One friend of mine bought the AQ cables mentioned earlier, I would neeeeever pay those money for a cable even though it was an improvement to my earlier crappy Supra ply. I made my own which was even better then AQ and I paid $15 :) ain´t life sweet. Obviously it´s important for my friend to have gear that is "accepted" by the snobbish hifi-press, I´m not like that though. I trust my ears which are extremly good.

"As mikek and others have indicated, some here are always going to believe what THEY WANT TO BELIEVE, regardless of any technical explanations, regardless of published studies, regardless of psychoacoustics, and regardless of what anyone here says"

Aren´t my blind tests enough for you my friend? (what´s your name, mine is Peter).

"But it's not fair to try and shoot the messenger and accuse them of being deaf, dumb, drunk, listening to elevator music, etc--especially when no objective information is presented to support their attack."

I have not done anything of that. But it is a fact that all audible differences I mention are real and can´t be denied by anyone UNLESS the test is done (as I said earlier) with errors or factors that obviously can not lead to a positive result. If a person has good hearing and IF the listening is done in a room with controled acoustics and IF the speakers are high rez and IF the electronic chain is of good quality THEN swapping one component for another (even cables) WILL be audible for MOST people. cables. That IS a fact, anyone saying something else is wrong and have not learned much about high perfromance audio, that may sound hard/harsh to some ears but it´s true and it´s a fact.

"(even at the risk of being ridiculed by the GoldenEars like I have been)."

I really hope you are not feeling ridiculed by me, as that has absolutely not been my intention.

All I wanted to do in this thread is to tell the truth and not watch someone (no one particular) "bending the truth". "Newbies" and lurkers has the right to know that in the end, remarcable things can be achieved with the right gear and experience. It does not mean that I think everyone should aim for an extreme SOTA rig, but the option and the truth must be there for everyone interested.

I really wish I could invite you to my home, having a glass of Shiraz, lighting up some candles. dim the light, switch on the class A amps and listen to some good SACD/CD´s. While doing this swapping out some components back and forth, and BAAAHM, this discussion would come to an end.

Happy listening! :)

/Peter
 
Home of the brave...

Hi nw_avphile,

Thanks for being brave enough to start the thread. Many, including myself, would hesitate or shrink away from such an endeavour. I think that building a diy mixing board is easier.

Please do not think this has been a futile exercise (as I have maybe implied). I've actually learned quite a lot about what to listen for and what else can be measured. There is still more information to research and apply.

Just as you have learned something about human nature, I hope that others will have learned something too. I know that I have.

Regards,

:)ensen.
 
diyAudio Senior Member
Joined 2002
PO..PO...LITE.

Hi,

To nw_avphile - you have been unfailing polite and persistent

Polite?

Hmmm, to all that agree with his POV, yes.

Persistent?

ROTFLAO.

Never, ever have I seen anyone twisting and turning so much to get a silly point across.

He could have reduced the whole thread to a few posts if its' purpose would have been outlined clearly from the start.

Pure "Self"ishness if you ask me, :mafioso:
 
Nicwix said:
We can see that Peter is tiring, but nw_avphile is going stronger than ever !!!

He is persistant and polite, I agree. Reminds me of Jehovah Witness attitude. ;) But he convinced me enough to perform my own test and really see what it's all about. I can't add anything else constructive, without doing that test, that's why I'm tiring.;)
 
Pan said:
We can not hear a difference if there is no measurable difference, that is clear as a bell. I know some people beliewe in "magic" in hifi equipment, plaese do not put me in that camp.
[/B]

An then continues with this statement :

First of all I don´t think it´s so much a question about $, but to answer your question, yes I can easily hear difference between loudspeaker cables and caps to the Accuton tweeter I use.
[/B]

Can you really say this with a straight face ? Or do you really understand what are you talking about here ? Any idea how much residuals will be there that are introduced by speaker cable ?

How about this experiment : disconnect your left speaker and connect it between amp's right 'hot' terminal and right speaker input 'hot' terminal.
(this in fact isn't valid test as you will have the 'good' voltage drop on the cable superimposed on top of the distortion component, pure resistive component doesn't cause any distortion so we should in fact remove it; but it will give you SOME idea about the magnitudes we're talking about).
Sit back and report how much signal can you hear from the left speaker.

Bratislav
 
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