Car Stereo is the #1 Car Audio Online Resource for radio,speakers, MP3, amps, subwoofers, box enclosures, IASCA,DB Drag Racing, USACi and MECA events Car Stereo is the #1 Car Audio Online Resource
Car Stereo is the #1 Car Audio Online Resource
Car Stereo is the #1 Car Audio Online Resource  Welcome to CarStereo.com the Internet Guide to Car Audio Car Stereo is the #1 Car Audio Online ResourceMY ACCOUNT   
Car Stereo is the #1 Car Audio Online Resource
OnlineCarStereo.com
The best and biggest selection of mobile audio/stereo, multimedia/navigation and accessories at the lowest prices! Kenwood, Pioneer, Rockford Fosgate, JVC, Sony, Clarion, Jensen, Infinity, Kicker and more...
Car Audio Black Friday Sales!
Message Forums Car Stereo Message Forums > Amplifiers > Class D Vs. Class A/B
Go Back Pages (1): [1]
Author
Thread Post New Thread    Post A Reply
mtaalib
Member

 Class D Vs. Class A/B

i am new here and i wanted to start a discussion about class d vs. class a/b. i know there are a lot of companies that make class d amps. but how many of you can say that a class d can compete w/ a class a/b in sound quality? we all know that a class d is more efficient and a class d is generally smaller in size. but what about cost per watt? or the benefit of using one or the other? we all know that most class d amps are limited to the sub regions (5hz-500hz). but there are some that are full range such as the zapco c2k-9.0. actually this amp is a class d(t) design. but it can function as a full range amp. if focusing only on the sub region, is the class d a better amp to use than the class a/b? why or why not? or is the class d a cheater amp for those w/ electrically challenged vechicles? does a class a/b amp actually sound better? i encourage you to respond to this thread w/ your opinions.

Report this post to a moderator

New Post 03-11-2004 02:50 AM
Click Here to See the Profile for mtaalib Click here to Send mtaalib a Private Message Find more posts by mtaalib Add mtaalib to your buddy list Edit/Delete Message Reply w/Quote
neal00
Member

 

Ok here's my 2 cents, although I don't have the experience to comment on all that you asked. I think watts per dollar would go to class D, you can get so much for so little nowadays. Not to mention there aren't that many 1200 watt and up class A/B amps. For me I guess it comes down to this, why would I spend more money, use up alot more space, and put more strain on my electrical system, when I don't have to.

Report this post to a moderator

New Post 03-11-2004 06:39 AM
Click Here to See the Profile for neal00 Click here to Send neal00 a Private Message Find more posts by neal00 Add neal00 to your buddy list Edit/Delete Message Reply w/Quote
N2Audio
Member

 

Neal pretty much summed it up.

In blind tests listeners can't differentiate A/B and D powering subs, and there's no reason they should.

I don't think there's much of an advantage for low power systems, but if you're running 1000 watt (or more) subs there's really no reason NOT to go class D.

Report this post to a moderator

New Post 03-12-2004 11:48 AM
Click Here to See the Profile for N2Audio Click here to Send N2Audio a Private Message Find more posts by N2Audio Add N2Audio to your buddy list Edit/Delete Message Reply w/Quote
mtaalib
Member

 

well, thanx for your input. i for one prefer to think of classs a/b vs class d as being application specific. if i'm designing a system i like to classify them as being one of two classes: sound quality or spl. if i'm designing a system w/ sound quality in mind there are a certain class of amps that i would use. this assumes price, space, and the electrical system is not an issue. i would use tube amps for the mids and highs. i would use a class a/b for subs. i would set up the system for active processing. that means no passive x-overs. these class of amp, in my opinion, would yield the best sound quality of any other setup. if designing a system for spl and space or price or the electrical system is an issue, then class a/b for mids and highs w/ a class d for subs would be my combination of choice. in this case passive x-overs would be use to minimize the number of amps needed for the system. some may say that there is no sonic difference between class d and class a/b at the lower end of the frequency band. to them i say that you don't get something for nothing. yes class d is more efficient. yes class d is cheaper and the amps smaller. but what about performance. clip a class d on your subs and see what happens. in a world of trade offs you must realize that there is no such thing as a perfect amp.

Report this post to a moderator

New Post 03-14-2004 11:59 PM
Click Here to See the Profile for mtaalib Click here to Send mtaalib a Private Message Find more posts by mtaalib Add mtaalib to your buddy list Edit/Delete Message Reply w/Quote
N2Audio
Member

 RE:

quote:
Originally posted on 03-14-2004 by mtaalib
well, thanx for your input. i for one prefer to think of classs a/b vs class d as being application specific. if i'm designing a system i like to classify them as being one of two classes: sound quality or spl. if i'm designing a system w/ sound quality in mind there are a certain class of amps that i would use. this assumes price, space, and the electrical system is not an issue. i would use tube amps for the mids and highs. i would use a class a/b for subs. i would set up the system for active processing. that means no passive x-overs. these class of amp, in my opinion, would yield the best sound quality of any other setup. if designing a system for spl and space or price or the electrical system is an issue, then class a/b for mids and highs w/ a class d for subs would be my combination of choice. in this case passive x-overs would be use to minimize the number of amps needed for the system. some may say that there is no sonic difference between class d and class a/b at the lower end of the frequency band. to them i say that you don't get something for nothing. yes class d is more efficient. yes class d is cheaper and the amps smaller. but what about performance. clip a class d on your subs and see what happens. in a world of trade offs you must realize that there is no such thing as a perfect amp.

a clipped amp is a clipped amp, and clipping always has the same effect - it dumps WAY more power into the speaker than the same amp in its full power unclipped state. A clipped 1000 watt a/b amp will blow a sub just as easily as a 1000 watt class D amp.

Report this post to a moderator

New Post 03-15-2004 02:36 PM
Click Here to See the Profile for N2Audio Click here to Send N2Audio a Private Message Find more posts by N2Audio Add N2Audio to your buddy list Edit/Delete Message Reply w/Quote
mtaalib
Member

 

actually that is not entirely true. when a class d amp clips, it puts out a dc signal. not only does it do this but it also looses control of the sub it is playing. this is very damaging for a sub and quickly kills it. why do you think class d amps are notorious for destroying subs? what do you think people mean when they say that class d amps clip "very hard"? it is because of the dc signal it produces when it clips, which is almost instant death to a sub. on the other hand, when a class a/b amp clips the amp still has control of the sub and still produces an ac signal. albeit w/ the peaks cut off, as seen on an oscilliscope, but at least it doen't fry the sub as quickly as a class d would. besides, if class d amps were such wonderful amps, why are they not being used by audiophiles for high-end home audio? don't get me wrong, i'm not saying that there is no use for a class d amp. i'm just saying that like all things, class d amps have a place. that place is where sound quality, space, price or the electrical system of the vehicle is an issue.

Report this post to a moderator

New Post 03-16-2004 03:10 AM
Click Here to See the Profile for mtaalib Click here to Send mtaalib a Private Message Find more posts by mtaalib Add mtaalib to your buddy list Edit/Delete Message Reply w/Quote
neal00
Member

 

mtaalib, I think most of what you say has merit. I was unaware that Class D amps clipped so hard. In one install that I did, I used a JBL BP1200.1 and I'm almost positive that I clipped the amp. But the sound from the woofers was not that much different than when I clipped the signal before the amp. It seems to me that if it threw out as much DC as you say it should sound very different. Maybe the JBL has a DC protection circuit, I don't know. The current crop of car audio Class D amps do have higher THD and lower damping factors, those are established facts. However in the next decade we will see many more full range Class D amps and probably some very good sounding ones too. The technology already exists for audiophile performance in a Class D circuit. Have you ever heard of Tact Audio? They introduced an audiophile Class D home amp five years ago. As for the sound quality of the Class D amps that are out right now, I think 99.9% of the people don't care or can't hear the difference. If I were to build my ultimate system, I would do something very similar to what you would do. But I would probably do an A-B comparison between D and A/B to see if I could really hear the difference

Report this post to a moderator

New Post 03-16-2004 06:02 AM
Click Here to See the Profile for neal00 Click here to Send neal00 a Private Message Find more posts by neal00 Add neal00 to your buddy list Edit/Delete Message Reply w/Quote
N2Audio
Member

 RE:

quote:
Originally posted on 03-16-2004 by mtaalib
actually that is not entirely true. when a class d amp clips, it puts out a dc signal. not only does it do this but it also looses control of the sub it is playing. this is very damaging for a sub and quickly kills it. why do you think class d amps are notorious for destroying subs? what do you think people mean when they say that class d amps clip "very hard"? it is because of the dc signal it produces when it clips, which is almost instant death to a sub. on the other hand, when a class a/b amp clips the amp still has control of the sub and still produces an ac signal. albeit w/ the peaks cut off, as seen on an oscilliscope, but at least it doen't fry the sub as quickly as a class d would. besides, if class d amps were such wonderful amps, why are they not being used by audiophiles for high-end home audio? don't get me wrong, i'm not saying that there is no use for a class d amp. i'm just saying that like all things, class d amps have a place. that place is where sound quality, space, price or the electrical system of the vehicle is an issue.

Not sure where you've gotten your info but there have been extensive debates about this exact topic in a couple highly technical forums involving some of the more respected people and companies in the indurstry. It's been established that clipping is clipping. It has nothing to do with amplifier class, and is simply a matter of power, not the method by which the power's generated.

The DC current thing is a myth too. A square wave isn't DC.

If I had to speculate I'd say class D amps are often associated w/blown speakers because generally they're very powerful, and cheaper for the power than class AB's. Most any newby can afford 1000 watt class D amps to run their pyramid subs - crank the gains and there ya go. Put 2 and 2 together.

And who says audiophiles don't use class D?

I've got a couple links if you'd like to read up.

Report this post to a moderator

New Post 03-16-2004 05:30 PM
Click Here to See the Profile for N2Audio Click here to Send N2Audio a Private Message Find more posts by N2Audio Add N2Audio to your buddy list Edit/Delete Message Reply w/Quote
mtaalib
Member

 RE:

quote:
Originally posted on 03-16-2004 by neal00
mtaalib, I think most of what you say has merit. I was unaware that Class D amps clipped so hard. In one install that I did, I used a JBL BP1200.1 and I'm almost positive that I clipped the amp. But the sound from the woofers was not that much different than when I clipped the signal before the amp. It seems to me that if it threw out as much DC as you say it should sound very different. Maybe the JBL has a DC protection circuit, I don't know. The current crop of car audio Class D amps do have higher THD and lower damping factors, those are established facts. However in the next decade we will see many more full range Class D amps and probably some very good sounding ones too. The technology already exists for audiophile performance in a Class D circuit. Have you ever heard of Tact Audio? They introduced an audiophile Class D home amp five years ago. As for the sound quality of the Class D amps that are out right now, I think 99.9% of the people don't care or can't hear the difference. If I were to build my ultimate system, I would do something very similar to what you would do. But I would probably do an A-B comparison between D and A/B to see if I could really hear the difference

well that is news to me. til now i did not know that high end class d audiophile amps were even made. shows how much i know. thanx for the info. as far as your last comment...i'd have to agree. i think mos people don't care.

Report this post to a moderator

New Post 03-17-2004 05:20 AM
Click Here to See the Profile for mtaalib Click here to Send mtaalib a Private Message Find more posts by mtaalib Add mtaalib to your buddy list Edit/Delete Message Reply w/Quote
mtaalib
Member

 RE: RE:

quote:
Originally posted on 03-16-2004 by N2Audio
Not sure where you've gotten your info but there have been extensive debates about this exact topic in a couple highly technical forums involving some of the more respected people and companies in the indurstry. It's been established that clipping is clipping. It has nothing to do with amplifier class, and is simply a matter of power, not the method by which the power's generated.

The DC current thing is a myth too. A square wave isn't DC.

If I had to speculate I'd say class D amps are often associated w/blown speakers because generally they're very powerful, and cheaper for the power than class AB's. Most any newby can afford 1000 watt class D amps to run their pyramid subs - crank the gains and there ya go. Put 2 and 2 together.

And who says audiophiles don't use class D?

I've got a couple links if you'd like to read up.


what i should have written is that a clipped signal from a class d amp has a higher amount of enery one one side of the waveform. this type of output exibits the same characteristics as a dc signal which when applied to a sub eventually causes the voice coil to go south. as far as the audiophile class d amps...i have learned something from you too. i was not aware that high end class d audiophile amps existed. thanx for the input and shoot me those links. i'm sure it will make for some interesting reading.

Report this post to a moderator

New Post 03-17-2004 05:22 AM
Click Here to See the Profile for mtaalib Click here to Send mtaalib a Private Message Find more posts by mtaalib Add mtaalib to your buddy list Edit/Delete Message Reply w/Quote
N2Audio
Member

 

This link -
http://www.carsound.com/cgi-bin/UBB_CGI/ultimatebb.cgi?ubb=get_topic;f=1;t=017258

And the link in that thread cover A LOT of ground. People almost lost their jobs for publicly claiming Class D's are more likely to blow subs than class a/b's.

Report this post to a moderator

New Post 03-17-2004 09:44 AM
Click Here to See the Profile for N2Audio Click here to Send N2Audio a Private Message Find more posts by N2Audio Add N2Audio to your buddy list Edit/Delete Message Reply w/Quote
thcisnice420
Member

 

audiophile grade class d amps.........any recommendations of companies that have these SQ class D amps, besides McIntosh Zapco US Acoustics JL and MMats........definitly in the market right now for a 1 ohm stable SQ amp pushing reoughly between 1000 and 1500 watts....

Report this post to a moderator

New Post 03-27-2004 03:51 AM
Click Here to See the Profile for thcisnice420 Click here to Send thcisnice420 a Private Message Find more posts by thcisnice420 Add thcisnice420 to your buddy list Edit/Delete Message Reply w/Quote
neal00
Member

 

Bud, (pun intended) you need to lay off that 420 and read this thread more carefully, we were refering to class D home amplifiers.

Report this post to a moderator

New Post 03-27-2004 06:02 AM
Click Here to See the Profile for neal00 Click here to Send neal00 a Private Message Find more posts by neal00 Add neal00 to your buddy list Edit/Delete Message Reply w/Quote
Author
Thread Post New Thread    Post A Reply
Go Back Pages (1): [1]

Show Printable Version  |   Email this Page  |   Subscribe to this Thread


   
 Recently Logged In Members  
RampagesZ, from Mobile, AL. Dayton605, from Dayton, TX. soltany, from beirut, MI. Rol886, from Rockaway Beach, NY. 2rgrbn, from Long Beach, CA. kaotiksyko, from , CO. banelsonms, from Moss Point, MS. weezer4rock, from , . jaboran, from swanton, OH. N2Audio, from Lawrence, KS. wolfantry, from erie, PA. IBBumpin, from Columbus, NE. tjsaudio, from anytown, MI. punkroc719, from Winchester, VA. Andrew, from Linden, MI. #1audio, from newport, NC. torawi01, from Corpus Christi, TX. Stripedss, from Hampton, GA. NRred2, from New York, NY. becesaudio, from davao city, AL.
see more member photos  post your members photo

 

 

 previous page Back Email this page to a Friend 
Home  |  Contact Us  |  About Us  |  Advertise  |  Join!  |  Log-In
 
Copyright © 2006 Online ConneXions Inc.
Web Designed & Hosting