1000 watts in Class D and Class AB

[cleansoundzz 10+ year member]

Is there a difference in clarity, sound and overall SPL between 1000 watts of power in Class AB amps than that with Class D amps? I hear people say that the clarity and musical sound of class AB amps is much preferred than that of class D amps. I also hear people say that 1000 watts in class AB is much stronger than 1000 watts in class D amps. Is this true?

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[bonesninja 5,000+ posts]

In double blind listening tests, they have proven that no one can consistantly pick whether they hear class ab or class d.....many people will disagree but they are full of shit.

And 1000 clean watts is 1000 clean watts...altho i do believe that AB amps generally draw more amps than do class d based on efficiency. Probably not 100% true but generally

 

[SHOemup233 10+ year member]

In double blind listening tests, they have proven that no one can consistantly pick whether they hear class ab or class d.....many people will disagree but they are full of shit.

And 1000 clean watts is 1000 clean watts...altho i do believe that AB amps generally draw more amps than do class d based on efficiency. Probably not 100% true but generally

Exactly.

Double blinds people can't tell the difference.

Clean power is clean power.

AB amps are much less efficient though than D, which is why many use D to run subs.

 

[NewAgeKing 5,000+ posts]

I ran class a/b orions for years. On components and subs. Only diffference i could really tell is the orions ran hotter. If you going anywhere between 0-1000 watts then someone may think one sounds better than the other. Beyond 1000 watts i dont really see any need for clarity, all your getting is loud beyond that point.

 

[Horsemanwill 10+ year member]

just to contradict i'ma say yes and i like ab better

 

[gunz4me 10+ year member]

I can't tell the difference between class a/b or class d on subwoofers.

When it comes to the class D full range series, it seems that the Alpine PDX amps lack balls in the midbass area. Could have been my friend's setup, but the midbass output from his 6.5" Type R is nothing like my 6.5" Type R. He has a 94 Civic hatch and no sound deadener in the doors, so that may be the difference too....

 

[Image Dynamics 10+ year member]

just to contradict i'ma say yes and i like ab better

I agree with Horseman...

There is an audible difference between class AB and class D amplifiers. Class AB does not throw the distortion levels that class D amplifiers do. For those that actually appreciate sound quality you can hear a difference. True that "clean power is clean power" however class D amplifiers ARE NOT CLEAN by any means.

Class D amplifiers will continue to increase their power output 3-4X their rated power as the distortion level increases from 1% to 5% to 10%. Class AB amplifiers actually run into a wall as distortion levels increase.

Regarding efficiency, class D amplifiers ARE more better than class AB amps at 4 ohms by 10-15% however as the amplifiers load down (1ohm) the difference is 2-3% at best. Are most poeple running class D amplifier at 4 ohm.. NO! most will run them at 1ohm. So is there a difference minimal at best.

For me, not enough to sacrifice the sound quality of a good class AB.

 

[n2audio 5,000+ posts]

ID

I don't know what it is you guys have against class D amps, but I recall a while back an ID "tech" having to eat a sizable serving of crow on CS regarding a claim that class D's are more likely to damage subs vs a/b based only on the topology of the amps.

It seems you're going the "poor sq" and "not much efficiency improvement" route now, but still without much factual evidence to support your case.

Class AB does not throw the distortion levels that class D amplifiers do. For those that actually appreciate sound quality you can hear a difference. True that "clean power is clean power" however class D amplifiers ARE NOT CLEAN by any means.

Does not "throw the distortion levels"??

You're right that Class ab tends to run with slightly less THD vs a class D, but you're wrong that it would have any appreciable effect on audible output.

I don't know how many THD vs Power charts you've looked at, but I think you'd benefit by looking at a lot more.

You'll find that even the budget class D's typically hover in the 1/2% range in the listening zone. Only approaching 1% at or very near rated output, which, coincidentally, is the same point that a/b's are spec'd for power.

Class D amplifiers will continue to increase their power output 3-4X their rated power as the distortion level increases from 1% to 5% to 10%. Class AB amplifiers actually run into a wall as distortion levels increase.

3-4x huh?? Wow. News to me. They must be putting some SERIOUSLY over-built power supplies in those amps. Think of the money they must be wasting!

FWIW - a fully clipped sine wave has 2x the power of its unclipped counterpart. What do they do? Inject super-duper sub killer power beyond that point??

And again - if you think a/b's run into some sort of magic THD wall at/near rated power you should really be seeking out more bench test charts.

Regarding efficiency, class D amplifiers ARE more better than class AB amps at 4 ohms by 10-15% however as the amplifiers load down (1ohm) the difference is 2-3% at best.

Simply not true. Some of the biggest, baddest class D sub amps can run at over 80% efficient at 1 ohm producing muti KW.

I have never seen a class a/b even approach 70% at full unclipped output at any impedance.

I think you might be better off sticking to marketing.

 

[DonH 5,000+ posts]

I agree with Horseman...
There is an audible difference between class AB and class D amplifiers. Class AB does not throw the distortion levels that class D amplifiers do. For those that actually appreciate sound quality you can hear a difference. True that "clean power is clean power" however class D amplifiers ARE NOT CLEAN by any means.

Class D amplifiers will continue to increase their power output 3-4X their rated power as the distortion level increases from 1% to 5% to 10%. Class AB amplifiers actually run into a wall as distortion levels increase.

Regarding efficiency, class D amplifiers ARE more better than class AB amps at 4 ohms by 10-15% however as the amplifiers load down (1ohm) the difference is 2-3% at best. Are most poeple running class D amplifier at 4 ohm.. NO! most will run them at 1ohm. So is there a difference minimal at best.

For me, not enough to sacrifice the sound quality of a good class AB.

haha more better! sry but hey! U live in the same city as me! NICE! me... born and raised in Ontario!

 

[squeak9798 5,000+ posts]

There is an audible difference between class AB and class D amplifiers.

Prove it.

So far, every possible effort that would prove such a statement as failed to come to that conclusion. In fact, just the opposite conclusion has been reached.

Class AB does not throw the distortion levels that class D amplifiers do.

So class A/B aren't capable of excessive levels of distortion //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

For those that actually appreciate sound quality you can hear a difference.

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

Sorry, but that was just funny.

True that "clean power is clean power" however class D amplifiers ARE NOT CLEAN by any means.

So being able to produce rated power output with 1% or less THD is not clean power //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

I guess you are going to have to clarify what exactly "clean power" is, and how a class D amp is not capable of achieving it when they are certainly capable of operating with inaudible levels of distortion.

Class D amplifiers will continue to increase their power output 3-4X their rated power as the distortion level increases from 1% to 5% to 10%. Class AB amplifiers actually run into a wall as distortion levels increase.

//content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif It's called clipping, and class A/B's will do exactly the same thing //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

Not 3-4x the power on either front, but as I see n2audio pointed out a full square wave is 2x the average power of a pure sine wave. And an A/B amp will do the exact same thing.

I'd really like to see graphs and measurements of this claimed 3-4x the power output, though. I'm sure many SPL amps could use such for pretty effective marketing.

Regarding efficiency, class D amplifiers ARE more better than class AB amps at 4 ohms by 10-15% however as the amplifiers load down (1ohm) the difference is 2-3% at best. Are most poeple running class D amplifier at 4 ohm.. NO! most will run them at 1ohm. So is there a difference minimal at best.

Just to play your game.....those efficiencies are also at full power output. How often do people listen to pure sine waves at full tilt?

Most amplifiers will spend the majority of their life averaging around the 1/3 power level. What's the difference in efficiency at 1/3 power //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Most class D's will still be in the 60-80% range, while class A/B's are hovering around 30-35%.

For me, not enough to sacrifice the sound quality of a good class AB.

I think somebody needs to step out of the marketing department.......

 

[FoxPro5 5,000+ posts]

just to contradict i'ma say yes and i like ab better

So do I. From what I've seen....and maybe it's just because there are far more A/B designs available on the market than D.....you can get more of what you want in features, layout, size and other factors in A/B amps than D.

But I'm not going to say I like Class A/B sound better than Class D sound because I've learned better. I cannot hear topology, nor can anyone else...so it's irrelevant.

 

[FoxPro5 5,000+ posts]

I guess you are going to have to clarify what exactly "clean power" is, and how a class D amp is not capable of achieving it when they are certainly capable of operating with inaudible levels of distortion.

What are the chances he comes back with something like: Oh, yea! Well you're going to have to define "operating" or "capable" or "levels"....or...or...."it." //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

 

[Horsemanwill 10+ year member]

man talk about dejavu we've been through this before lol that's y i posted my one thing and left but now it's starting back up.

 

[FoxPro5 5,000+ posts]

we've been through this before

That's because guys like N2, Squeak, and myself don't cut manufacturers any slack with their BS. And it's sad to see so many buy into it thinking they think they know what they think they hear. Just cuz it ca.com doesn't meen u haveta check ur brain at the door. Or does it? //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[squeak9798 5,000+ posts]

man talk about dejavu we've been through this before lol that's y i posted my one thing and left but now it's starting back up.

Honestly, I was going to leave this thread alone until I saw a representative of a manufacturer respond with rubbish......