A/B vs Class D for Subwoofer SQ

[Papermaker85 5,000+ posts]

i will agree with RC with no clipping and less than 1%THD its very hard to tell the difference in a very high quatitly installaion.. if you by pass xovers etc... it can BE below the theshold of the human ear...

but in a real world installation, different amps clip differently.. some more rapid.. slew rate changes at different rates, dampning factor etc... some amps use 10%some 5% some 1% on the tolarences.. is it better? yes and no... yes because your product is much closer in every measureable catogory to one another(IE output,SN etc..) most installations aren't "ideal" and aren't set up with i Oscopes and bypassed crossover networks etc... this is WHY companies are able to claim and charge more.. some xover networks use 10% tolarences in there swiching supplies and crossover networks, while others use 1%... you might have a specific amp that has a A/N of 90db while another same board parts etc.. has 92db...

I am a firm believer in high quatily parts in amps, just like in woofers and anything for that matter.. under real world circumstances there is a difference.. now it was said eariler, if you use good quatitly amps properly tuned there won''t be a difference, as in you won't beable to identify class of amplification..

what DOES make a big different is how well the amp is when its out of its linear range this is where the larger power supplies, tighter tolerances in swiching supplies and x-overs etc.. come into play..

so if your going to get an amp a cheap amp chances are its not going to sound as good as a high quatitly amp, simply because your going to exceed its linear output.. on the other hand if you get a decent amp and properly tune it chance are you won't hear a difference..

 

[rc10mike 10+ year member]

So just because nobody as passed the test 100% with 24 correct responses = all amps sound the same? Since he doesnt keep detailed records, what about all the people that may have come close?

And about the one that got 8 correct and they went back and claimed the settings were off

 

[bass_lover1 10+ year member]

I though Richard Clarks' test was to compare 2 amps, one low end and one high end, and u tell him which one is which? I didnt think it was to tell the difference between amp classes?
Anyway I love good sound quality. With that being said I am far from a SQ setup. My best sounding system was in my 91 Prelude. I had linear power 2502 iq's running. I had 3 of them i for the front mids and highs, and 1 for each sub. It was the most musical setup I have ever had. My friends still talk about it. I dont know how much the a/b amps impacted that. I think the actual vehicle you use is extremely relevant in SQ. Install, things like tweeter location are very important too. So what am I saying? My one remaining LP amp is still my fav amp, but I run a class d to my sub(s) these days because the current draw of a/b is just too much. I have a pro audio amp crest audio cd2000. It is a full range class d. I think it sounds better than the cc 1800 a/b that it replaced. So I cant choose a side.

You wouldn't happen to be willing to part with that 2502IQ? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[FoxPro5 5,000+ posts]

nvmd...it's not worth it...

 

[mcsoul 10+ year member]

If they restrict the gain on one amp and eq one of them to where they are equal on an rta, they

will sound the same; no big surprise. It will be hard as heck to tell which one is which.

 

[gunz4me 10+ year member]

If they restrict the gain on one amp and eq one of them to where they are equal on an rta, theywill sound the same; no big surprise. It will be hard as heck to tell which one is which.

We can't leave out the fact that these amplifiers are played at a threshold that is WAY below clipping! I wish anyone luck in being able to pick out the difference there...

 

[tRiGgEr 5,000+ posts]

Tubes

 

[DEdwards 10+ year member]

Stated "Challenge" was with solid state amplifers only.

 

[mud 10+ year member]

As an engineer, these kind of threads make me laugh. The same way that those threads about the merits of ridiculously expensive signal cables for home audio make me laugh.

//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif//content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

 

[DidUHearThat? 10+ year member]

Stated "Challenge" was with solid state amplifers only.

No. It started with studio grade tube versus solid state, once he had settled that pissing match he moved on to car audio amps. The info clearly says any amps.

 

[DEdwards 10+ year member]

hmmm....so a Butler Tube amp vs. a Pyle amp.....hmmm

 

[gunz4me 10+ year member]

hmmm....so a Butler Tube amp vs. a Pyle amp.....hmmm

Yes but with EQing to place them on a level playing field as well as running them way below clipping. If it wouldn't be for that little EQing part, you probably would be able to tell the difference. Why else do you think that RC hasn't given any of his hard earned money away?

 

[DidUHearThat? 10+ year member]

Yes but with EQing to place them on a level playing field as well as running them way below clipping. If it wouldn't be for that little EQing part, you probably would be able to tell the difference.

You keep making these BS claims while it's obvious you haven't taken 2 minutes to actually read the challenge or the FAQ.

It's obvious you have no idea wtf your talking about.

I'll explain it to you in small words.

Eqing is ONLY used when one amp exibits a frequency change durring set up. Which it shoudn't, but if it does, that would make it easy to identify.

Then...

The listener can switch the eq back and forth between amplifiers. So you can a/b the amps with and without the eq, except you don't know which.

All signal processing circuitry (e.g. bass boost, filters) must be turned off, and if the amplifier still exhibits nonlinear frequency response, an equalizer will be set by Richard Clark and inserted inline with one of the amps so that they both exhibit identical frequency response. The listener can choose which amplifier gets the equalizer .
Is adding an equalizer just a way of “dumbing down” the better amplifier ?

Richard Clark allows the equalizer to be added to whichever amplifier the listener wants. It can be added to the amplifier that the listener perceives as the weaker amplifier . The EQ is most likely to be used when comparing a tube amplifier (which exhibits slight high frequency rolloff) to a solid state amplifier . In that case Richard Clark says he can usually fashion an equalizer out of just a resistor and/or capacitor which for just a few dollars makes the solid state amplifier exhibit the same rolloff as the tube amplifier, and therefore sound the same. If the tube amplifier really sounded better, then modifying the solid state amplifier to sound indistinguishable from it for a few bucks should be a great improvement.

Why else do you think that RC hasn't given any of his hard earned money away?

Because there is no audiable difference between amp types. Which is the point of this thread.

 

[DidUHearThat? 10+ year member]

hmmm....so a Butler Tube amp vs. a Pyle amp.....hmmm

Another genius that can't read.

Do the results indicate I should buy the cheapest amp? No. You should buy the best amplifier for your purpose. Some of the factors to consider are: reliability, build quality, cooling performance, flexibility, quality of mechanical connections, reputation of manufacturer, special features, size, weight, aesthetics, and cost. Buying the cheapest amplifier will likely get you an unreliable amplifier that is difficult to use and might not have the needed features. The only factor that this test indicates you can ignore is sound quality below clipping.

If you have a choice between a well built reliable low cost amp, and an expensive amplifier that isn't reliable but has a better reputation for sound quality, it can be inferred from this test that you would get more sound for your money by choosing the former.

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

 

[DEdwards 10+ year member]

Another genius that can't read.


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

a simple statement and now I can't read?//content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif I have read the FAQs and know the challenge very well....you can now get off of your high horse....this thread is useless anyway and any of the threads that talk about this subject always end the same...I am also the one that stated you can't hear the differance in Class A/B and Class D....I can't...the judges all year couldn't and doubt anyone here could....