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The Richard Clark "all amps sounds the same" test


Okay, I know there has been tons of commentary on this issue, but I have a specific question. And it will make it clear why I'm posting this amp question in the speaker threads.

I'm curious if anyone knows if Maggie 20.1s or something equally hard to drive and equally transparent has been tested? I know planars have been used on his test, but I don't know any details.

Oh - for those who don't have any idea what I'm talking about see:

http://www.tom-morrow-land.com/tests/ampchall/rcrules.htm
and
http://www.tom-morrow-land.com/tests/ampchall/index.htm

and if you google it there is almost endless commentary on it.

Okay - but I want to test the following:

Magnepan 20.1s
Pass Labs X350.5 or XA160.5
Pass Labs Pre? (Don't care as much)
EmmLabs CD Player

Then, we need a low-cost amp. Now, the trouble is, he has a reasonable request in his test, each amp has to be used within its thresholds, so no using them at 300 watts when one is rated at 30 watts. Obviously with one clipping and the other one not clipping you will hear a difference.

This also applies to a 4-ohm speaker. So, assuming someone hasn't done an extremely similar test and can just tell us the difference, the next question is what is the worst amplifier that is rated at 4 ohms? While the X350.5 is high-power, the test could be done at 85 db, so you don't need too many watts to make that work.

This would effectively answer all the "maggies need high power to by dynamic" and lots of other similar questions. Because the test is at one db level, does one amp really push more bass out of them than another?

Hey - actually wouldn't Tympani IVs be harder to drive? Maybe we should use Tympani's :).

What do people think, is this issue still alive or has someone resolved these issues? I have to think I could hear the difference and may have my wife run some singly-blind tests for me - I don't have any of the equipment above, but do have 3.6s and an Aleph 5. See how that Aleph sounds compared to some sort of $100 amp rated at 4 ohms.

Might there be a 4-ohm rated amp in a boombox or bookshelf system? I'll poke around. Sure a single op-amp chip in a bookshelf system (often what $100 system amps consist of, just a few chips) would sound worse than a Pass Labs Aleph, which Stereophile said compared to the Levinson 300 lb amps?

Oh - and the essence of my idea with this test is that perhaps the sound is 'more similar' on speakers that are easier to drive, but with 20.1s - and this is just as important - with a highly resolving ribbon speaker - the difference might become more apparent.

Oh - also, I'm not sure if he allows me to choose the music, but I have found over the years certain parts of certain passages that show the differences of components more than others. I think that would also be important - what passages are played, as on some I would believe the differences would be impossible/difficult to detect.

If I'm just repeating stuff that can be found elsewhere let me know... Just seems like we should be able to bust this test.
lightminer
lightminer OP
164 posts
 
Yeah, exactly. I just did the (dynamics, not amp a vs b) test mentioned above, and on the Shostakovitch disk got a couple of 105 db peaks and many, many over 100 db on a nominal level of 78 db. I was using fast / C weighting. Quite dynamic! I probably had it a little high - the level I normally listen to that track with has it opening at 76 db or so. And the meter can't really keep up with the quick changes - so it might be a tiny bit higher.
johnnyb53
3,510 posts
 
Gawd, I LOVE Shostakovitch. You can't have too much power in da house to play him back realistically.

I was fortunate enough to see Rostropovich conduct the Seattle Symphony Orchestra in April 2006 to commemorate Shotakovich's 100-yr birthday. I was sitting in the front row, about 4' from Rostropovich himself.

Now THAT was dynamic. I'm so glad I got to see Mischa one more time before he left us.
...the meter can't really keep up with the quick changes - so it [maximum SPL peaks] might be a tiny bit higher.
Count on it, like 110 dB or so. You could easily eat up 150 wpc powering Maggies playing Shostakovich.
mrtennis
3,295 posts
 
the alleged differneces between amps , following the restrictions established by mr clark, are irrelevant with respect to purchasing an amplifier.

if i am considering two amplifiers, a conrad johnson mv 125 adn some current solid state amp, i believe i will prefer one over the other all of the time.

in this case it is possible that the cj amp does not meet the criteria for a fair comparison.

it doesn't matter, because i would use the cj amp with a panel speaker and prefer it to any solid state amp anyone could provide.

my point is, in the real world of amplifiers, some tube amps will not sound the same as some solid state amps, for whatever reason.
atmasphere's avatar
atmasphere
11,577 posts
 
Mrtennis is right in his bottom line, and I can add to it: even if you add EQ to make a tube amp and solid state amp 'sound the same' isn't there a tacit admission there that they don't? Huh? I'm sorry, but in this case Mr. Clark has fooled himself silly.

Different amps in fact sound different. Here are the areas to look in which you will find immediately apparent, very audible differences: the differences between tube and transistor, within one camp of expertise, the difference between a class A amplifier and one that is not, and finally the difference between a zero feedback amplifier and one that uses feedback.

Areas to be sensitive to as you audition these amps: high frequency content; the sense of 'brightness' (even though all the amps might have the same bandwidth), differences in soundstage presentation (currently not a measurable quantity), presentation of the attack of the various instruments, smoothness as opposed to harshness, that sort of thing.

I could forecast some of the results but that might take the fun out of it for you :)

Soundlab or Magnaplanar 20.1- either is fine.
lightminer OP
164 posts
 
MrTennis and Atmasphere - give the guy a call. Here is one page with the info. Win the jackpot that a couple thousand people haven't won of $10,000 that he offers for winning!

http://www.tom-morrow-land.com/tests/ampchall/index.htm

But note that some of the things you mention (high frequency content; the sense of 'brightness') are things he will make equal with his eq, no?

The soundstage and attack (and perhaps decay as well?) - those are the places you might get it right. If you do give it a try I've heard from reading the threads about it that tracks with lots of voices tend to score higher, so include some voice stuff. But be confident, he charges 200 to take the test to limit serious requests. :)
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