[kingmajix]

I saw a link in another post to The Audio Critic (The Audio Critic) and I read a few of their back issues recently. It looks like Aczel has some pretty strong comments about amps (among other things). To paraphrase:

An amp is an amp and double-blind testing shows that no one can accurately pick out a sq difference in amp switching anywhere close to 100% of the time.

What do you guys think about this? I'm not intending to start a flame war but just a rational dialogue about some of the ideas put forth in TAC regarding amps, tubes, power cords/cables, etc. His strong opinions seem worthy of being discussed.

Scott

 

[JadeEast]

Quote:

Originally Posted by kingmajix /img/forum/go_quote.gif I saw a link in another post to The Audio Critic (The Audio Critic) and I read a few of their back issues recently. It looks like Aczel has some pretty strong comments about amps (among other things). To paraphrase: An amp is an amp and double-blind testing shows that no one can accurately pick out a sq difference in amp switching anywhere close to 100% of the time. What do you guys think about this? I'm not intending to start a flame war but just a rational dialogue about some of the ideas put forth in TAC regarding amps, tubes, power cords/cables, etc. His strong opinions seem worthy of being discussed. Scott

Hi Scott I think your post may be better served in the "sound science" section of the forum.

It's really the only sub forum where the topic of blind testing is encouraged.

 

[kool bubba ice]

Quote:

Originally Posted by kingmajix /img/forum/go_quote.gif I saw a link in another post to The Audio Critic (The Audio Critic) and I read a few of their back issues recently. It looks like Aczel has some pretty strong comments about amps (among other things). To paraphrase: An amp is an amp and double-blind testing shows that no one can accurately pick out a sq difference in amp switching anywhere close to 100% of the time. What do you guys think about this? I'm not intending to start a flame war but just a rational dialogue about some of the ideas put forth in TAC regarding amps, tubes, power cords/cables, etc. His strong opinions seem worthy of being discussed. Scott

& women are the same cause of their thingy's..

Ad Nausea here.. If he wants to believe a boostro sounds the same as a B52 fine. Or a ipod DAC to a 10,000 dac thats fine..

 

[Edwood]

I can blow his theory out of the water, double blind or not.

I'll just bring my K1000's.

-Ed

 

[Ferbose]

I think he is talking about power amplifiers for speakers.
Moreover, it is a power amplifier with unity gain, which is acting solely as a power amplification device.
There were blind tests performed in yesteryears on power amplifiers for speakers.
The claim was that as long as the amp is powerful enough and the damping factor is high enough, the listener could not tell the difference.
Of course the results were controversial.

But at least many people at the time saw the take home message being that voltage amplification may be much important than power amplification for sound quality in a speaker system.

Most power amplifiers today provide voltage gain, and therefore those tests may be ireelevant today.

 

[Wmcmanus]

I have no patience for people who think they know everything and then insist upon pontificating their great wisdom. I've read his stuff on several different occasions when someone (either here or at another forum) has linked to it, but it's always the same tired diatribe of, "I know everything; listen to me and nobody else." Ironically, these sorts of attempts to build up one's credibility have just the opposite effect, at least from my perspective. So whether he's right or wrong about something, I don't even care at this point. I just ignore him and move on. If anything he happens to say has merit, it will be proven by other people who have more credibility.

 

[Uncle Erik]

I managed to get the MV-52 to clip tonight.

Funny, the clipping sounded nothing like a solid state clip.

I've read a couple of articles on this and I think there was a challenge put forth over telling the difference between amps. But if you read the fine print, the amps aren't allowed to clip, they have to have substantially similar circuits, and so on. They wouldn't let you match up a 3W SET against a 100W MOSFET, for example. The reason they're afraid of that is pretty obvious.

 

[JadeEast]

Clipped from the website.

"all amplifiers having high input impedance, low output impedance, flat frequency response, low distortion, and low noise floor sound exactly the same when operated at matched levels and not clipped"

This is pertaining to loudspeaker loads how applicable is this to headphone amps? I'm not sure that anyone has done an objective leaning testing of headphone amps in a ABX or blind test at this point in time.

 

[LnxPrgr3]

Quote:

Originally Posted by JadeEast /img/forum/go_quote.gif This is pertaining to loudspeaker loads how applicable is this to headphone amps? I'm not sure that anyone has done an objective leaning testing of headphone amps in a ABX or blind test at this point in time.

Headphone amps are doing exactly the same job, except they're putting out much less power into a higher impedance load.

 

[monolith]

It makes some sense, if you think about it. I mean, the closer to ideal a given amp is, the more it should sound like other amps of the same caliber.

 

[PiccoloNamek]

Quote:

"all amplifiers having high input impedance, low output impedance, flat frequency response, low distortion, and low noise floor sound exactly the same when operated at matched levels and not clipped"

I have no doubt that this is completely and absolutely true.

I love the Audio Critic. It is a beacon of truth and rationality in what is otherwise a hobby full of almost nothing but lies and snake oil.

 

[Ferbose]

Quote:

Originally Posted by Uncle Erik /img/forum/go_quote.gif I managed to get the MV-52 to clip tonight. Funny, the clipping sounded nothing like a solid state clip. I've read a couple of articles on this and I think there was a challenge put forth over telling the difference between amps. But if you read the fine print, the amps aren't allowed to clip, they have to have substantially similar circuits, and so on. They wouldn't let you match up a 3W SET against a 100W MOSFET, for example. The reason they're afraid of that is pretty obvious.

I remember an old article by Ian Master on the Soundstage network website saying that in one of those tests, a low power SET tube amp was compared to a class A/B solid state amp and still the listeners could not tell the difference

. Of course all the participants, some of which have good credentials, all felt surprised and embarrassed. But let's not forget these tests are probably more about one's memory ability than listening ability.

I just came up with an analogy:

Have one person read out:
786544396254824439265234487652093
And then read this string of numbers
786544396254724439265234487652093

And ask the listener, do you hear a difference?
Of course the listener can hear that 8 sounds different from 7, but who can remember it in this context? It is confusing as hell.
The kind of listening test that is banned from discussion on this forum is also confusing as hell to the ear-brain. So I am going to follow the rule and not discuss it

 

[jonathanjong]

On an unrelated note, how do you like that Tivoli?

 

[Ferbose]

I don't have experience with good tuners, but I think the Tivoli radio sounds decent as a tuner. The speakers are small and distorted, but pretty pleasant sounding. The headphone jack works fine, but has too much midrange and too little treble. I would rather pair it with a brighter headphone like Koss KSC-35 than a smoother Senn PX100.

I can enjoy music on a Tivoli plus KSC-35.
I can also enjoy music on K1000 with first-rate DAC and tube amp.
And I don't need to pretend that an active electronic component in my system does not make a sonic difference to help me enjoy music.
To me it is quite absurd to think that an active amplification device would not influence the sound, when I am pretty sure that using the proper contact cleaner/lubricant on RCA connectors can help improve the sound of my system.

BTW, the contact cleaner is "CAIG ProGold," sold at Guitar Center and everywhere else for only $10. It is well known to electrical engineers that proper cleaning/lubrication reduces the signal distortion at metal-metal contacts. I really think it does more to the sound than any fancy cable/power cord I have tried.

 

[MoodySteve]

As an engineer, I do appreciate that the Audio Critic tries to evaluate audio technology and claims using more empirical methods than people's opinions. I think that the snake oil does deserve to be called out.

As an avid listener and DIYer, I think they sometimes take too strong a stance and discredit themselves in the process. They seem to have this notion that if there isn't a 'night and day' difference between two pieces of equipment (or before and after adding an 'upgrade') then one doesn't exist at all.

And from a pure emotional standpoint, I'm inclined to say 'Who are you to tell audiophiles not to enjoy their hobby?'. If Joe Audiophile thinks that his music sounds better with a pricy (CDP/Preamp/Amp/DAC/Cable/Cable Treatment/Vibration Treatment/etc etc etc) and he's happy to pay the price, I think Joe should be allowed to feel this joy. Why deprive someone of that? I realize I've long since left science and wandered into philosophy here.