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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
freewaywilly
7 posts
 
I have a Denon AVR and a Manley Stingray. Every once in awhile, I listen to the Denon. It sucks compared to the Manley. The difference is not subtle.
lightminer OP
164 posts
 
Cool - so do a 'home test' if you have the couple hours. (btw, that is a *very* cool looking amp.) Have someone get 12 tracks (I think that is what he suggests) put a sheet up over your stuff and have someone do the switching. Do the full abx test as he describes. He is picky about getting all 12 right.

I'm going to try it in next few days out of personal interest. One problem, though, is that reading enough info about this - a few people have gotten all 12 right, then he does level adjusting to within 1/10 of a db and then they don't pass the 2nd time. He doesn't like to start with all that level matching just because it takes a while. So keep that in mind - and this isn't in question - mild increases in volume can make piece A sound better than B whether it is CD player or whatever.

If you get it right, maybe you can make 10k. Or maybe its just bunk. I'll know more when I do the tests in a few days, maybe this weekend.
glowplug
37 posts
 
As much as i hate the idea he could be right, it does beg the question.....why hasnt anyone won yet!
oem
91 posts
 
Years back Bob Carver said that he could tweek his amp to sound like any other amp in the marketplace.
That statement suggests that Mr.Carver thought that amplifiers sounded different from each other.Not that he or anyone else needs my affirmation but I indeed agree that amplifiers have different sound.Isn't this challenge similar to another that M.F.of Stereophile debunked a few months back.The criteria for winning the prize keeps changing as one gets closer to the finish line.Forget about the test and just enjoy the music.
That said,I don't know why I am even taking the time to post on this thread
lightminer OP
164 posts
 
So, I've been looking for the 'cheapest' 4-Ohm rated amplifier I can find. This is one candidate:

http://www.onkyousa.com/model.cfm?m=TX-8222&p=i&class=Receiver

I have nothing against Onkyo - I was hoping for a much lower brand, but that is a $150 receiver and is rated at 4 OHMs for use, and should sound different than the high end Pass Labs stuff.

One of the problems I'm having is:

9. The amps will not be overloaded during the session from either a voltage or current requirement.

So, part of the Maggie 'thing' is that many amps would be current overloaded, and that is part of the point of getting an expensive amp. I do have a multimeter and could detect the amps or voltage at the terminals, but don't have the electronics to determine if the current will be overloaded on the cheaper amp.

All of this leads me to believe that the issue may be in the definition of the problem - you have to at least get to the Harmon Kardon/Rotel/NAD level to drive ribbons, electrostatics, or quasi-ribbon speakers without overloading the amp. A more interesting test might be, given a really really solid 1k amp, can 10 people detect the difference between that and a 10k amp - that is a much more subtle thing, but lets start here and see if we can resolve the $150 amp vs best amps in the world first.

And, regardless, I want to get 90% or better on the test (not necessarily 12/12 as is required for the 10k - but I do agree I would get 12/12 if I were comparing apples to oranges, which is what he is saying we say about amps and if I were giving away 10k I might also say 12/12.)

If anyone knows a 'worse' receiver or amp that says 4 Ohms somehwere in its manual let me know.
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