1000 watts in Class D and Class AB

[audiolife 5,000+ posts]

In a system to enjoy listening too I do not think I would ever want or need an amplifier that does 1000 watts at 1 ohm....not saying I wouldnt get a big amp or 3-6 subs but I do not think I would enjoy the music with a system like that as much...there is more to music than WanG.

 

[gunz4me 10+ year member]

Does anyone here remember hearing the first generation Class D subwoofer amplifiers? I do, and they were NOTHING to write home about. Even the custom shops didn't recommend them and they had to sell the darn things!

 

[microhaxo 10+ year member]

Hmm, i currently have a A/B amp (hifonics 1606d on the way) and i have heard many Class D monoblocks and i believe they sound the same. I think its all about the setup. Most of the Monoblock class D setups that i have heard have been improperly setup (gain too high, bass boost on) Etc.. My one friend runs two alpine mono's to his R's and he has them clipping like hell, 1300w from each 500w amp. I tuned it to exactly 500w each and it sounded nice and clean but it wasnt the loud fart that he was used to hearing so he turned em right back up.

Basically back to the point, if it is setup properly and is within range of the amp then i think it is really ambiguous to say that one sounds better than the other.

 

[squeak9798 5,000+ posts]

People try hard to defend class D amps. That's for sure.

It has nothing to do with defending class D.

It has to do with dismissing myths and abating ignorance.

I'd pose the same argument in a comparison between any two classes of amplifiers.....A, A/B, D, G/H, etc. A/B vs. D just happens to be the topic of this particular thread.

It's a matter of listening to the woofers rather than the environment.

Which can not be done unless you were listening to the driver free air in an anechoic chamber in highly controlled circumstances. The enclosure, the vehicle's acoustics, the placement of the driver in the vehicle, the specific settings pertaining to the subwoofer in that particular installation, the difference in power & gain structure between setups, the differences in resonance of the vehicles, etc etc etc. These are ALL going to play a role in the acoustics of the bass, and you will not be able to eliminate them in order to draw any kind of conclusion regarding the differences in sound caused by the class of the amplifier.

This goes right back to my earlier post about how people try to draw specific conclusions from completely meaningless "comparisons".

For me I like to unplug the RCA's from the mid amps to listen to the bass exclusively. With the mids and highs on in both vehicles it is hard to really listen to the bass clearly. Once I cut off the mids and highs the differences are really apparent.

And doing this is still completely and utterly meaningless in trying to determine differences in sound between "class" of amplifiers in two different installs in two different vehicles (even if, as N2Audio pointed out, they were identical subs.....which you've yet to outline the particulars of what the substage actually consists of in each install).

 

[loud-n-low 10+ year member]

so is the big debate between class a/b and class D fans all myth? based only off specs?

 

[AndyInOC 10+ year member]

you'll shoot your eye out kid!!!

 

[Louisiana_CRX 5,000+ posts]

you'll shoot your eye out kid!!!

WTF ...you smokin' crack or some other shit?

 

[gunz4me 10+ year member]

so is the big debate between class a/b and class D fans all myth? based only off specs?

If I had to explain some of the differences I have heard between class a/b and class d, I would say that class d tends to produce noise instead of music.

Granted, there are numerous factors that are at play here with the main factor being setup! The Cadence setup that I referenced in my other thread DID NOT have a proper electrical system. Maybe that is why the double bass pumps just blended together. Then again, he did have a capacitor (lol).

Could also be damping factor. By nature, most class D amplifiers have a lower damping factor than competing class a/b counterparts. I wouldn't put it past me to be one of those weirdos who can tell the difference based on that. After all, I hear artifacts in 320 Kbps MP3 compression that most others can't hear.

It could also be the fact that I was once a real musician who played trombone in a brass section. My brain is telling me something is wrong because I know how something is supposed to sound and when it sounds different than expected, it just sounds wrong.

Regardless, I have been involved in clinical trials before, and I am always the unlucky one who experiences something that 95% of the group DOES NOT experience.

 

[cleansoundzz 10+ year member]

It has nothing to do with defending class D.
It has to do with dismissing myths and abating ignorance.

I'd pose the same argument in a comparison between any two classes of amplifiers.....A, A/B, D, G/H, etc. A/B vs. D just happens to be the topic of this particular thread.

Which can not be done unless you were listening to the driver free air in an anechoic chamber in highly controlled circumstances. The enclosure, the vehicle's acoustics, the placement of the driver in the vehicle, the specific settings pertaining to the subwoofer in that particular installation, the difference in power & gain structure between setups, the differences in resonance of the vehicles, etc etc etc. These are ALL going to play a role in the acoustics of the bass, and you will not be able to eliminate them in order to draw any kind of conclusion regarding the differences in sound caused by the class of the amplifier.

This goes right back to my earlier post about how people try to draw specific conclusions from completely meaningless "comparisons".

And doing this is still completely and utterly meaningless in trying to determine differences in sound between "class" of amplifiers in two different installs in two different vehicles (even if, as N2Audio pointed out, they were identical subs.....which you've yet to outline the particulars of what the substage actually consists of in each install).

How many people are going to doing tests in controlled environments? Not many. Simply put, if I switch boxes switch amp temporarily in the same vehicle, I can tell the difference. Or if I listen to the same kind of music in different vehicles I can tell the difference in bass. Not how hard the bass hits but the clarity and musical tone of the bass. I listen to a lot of reggae and R&B not rap, so the differences are more apparent.

I talked to Steve Mantz last week about this and he said when mono blocks are driven at 4 ohms instead of 1 ohm did the differences between class D and class A/B are no longer significant. That is a better argument than hearing people go back and forth about the differences in sound.

 

[audiolife 5,000+ posts]

If your subs are in the trunk I do not really see how an average user would be able to "tell the difference". Also really doubt an "expert" could really tell just by listening because if they did not like the sound from the system with the Class D amp I really doubt they would like it any more or less with a A/B amp. I do think some amps are more set up friendly though with regards to how the gains work with respect to a deck. Some get real shitty real fast with less than a 1 hour bump on the gain where other amps seem to have a wider sweet spot when setting gains by ear. Seems the settings seem more linear if you understand where I am coming from.

 

[cleansoundzz 10+ year member]

My trunk is not a closed trunk. I have a 4 -Runner and a 300zx so the bass is open and exposed.

 

[squeak9798 5,000+ posts]

How many people are going to doing tests in controlled environments? Not many.

Exactly!

Nobody performs properly controlled experiments when doing these "comparisons"! So why do people continually attempt to draw any type of conclusions from them? The comparisons were not conducted in such a manor to give them that ability, to allow them to make any kind of valid conclusion. They can not claim that the difference they heard was the result of one single variable. It's a fallacy and ignorant.

Simply put, if I switch boxes switch amp temporarily in the same vehicle, I can tell the difference.

No, you can not.

You think you can, you've tricked and fooled yourself into believing you can. Because you are basing this conclusion off of a flawed, invalid, unreliable and inconclusive comparison/experiment. But in a properly controlled and double blind experiment, you would not be able to tell the difference.

Numerous experiments have been conducted that would prove exactly this....the audibility of amplifier "classes" (among other things). The test subjects have been everyone from amateur, to audiophile, to designer. And not one has passed the test. Not one has been able to identify an audible difference in amplifier class.

So what in the world makes you think you can? The flawed, invalid, inconclusive and unreliable tests you've "conducted".

Or if I listen to the same kind of music in different vehicles I can tell the difference in bass.

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

Really? You think this is a surprising result? You don't think there are dozens of variables at work here, and you haven't isolated a single one of them?

How do you think listening to the same song in different vehicles gives you even a remote iota of being able to claim that one specific variable was the reason for the difference you heard? You can't.

What do you not understand about valid, scientific, reliable testing?

 

[loud-n-low 10+ year member]

so keeping the same vehicle,same components,same subs,same song playing,just swapping out amps from class ab to class d, that is null and void totally also? not even somewhat comparable? is it fair to compare an a/b amp running 4 ohm mono to a class d amp at 1 ohm since this is how most,not all are ran?

 

[squeak9798 5,000+ posts]

If I had to explain some of the differences I have heard between class a/b and class d, I would say that class d tends to produce noise instead of music.
Granted, there are numerous factors that are at play here with the main factor being setup! The Cadence setup that I referenced in my other thread DID NOT have a proper electrical system. Maybe that is why the double bass pumps just blended together. Then again, he did have a capacitor (lol).

In the first paragraph you attempt to draw a conclusion about a difference in sound between amplifier classes.

Then in the next paragraph, you openly state that the comparisons were not conducted in a way that would allow you to draw any kind of conclusion.

So why even state the first paragraph, when you later openly admit that it is flawed?

Could also be damping factor. By nature, most class D amplifiers have a lower damping factor than competing class a/b counterparts. I wouldn't put it past me to be one of those weirdos who can tell the difference based on that. After all, I hear artifacts in 320 Kbps MP3 compression that most others can't hear.

No. The damping factor of just about any solid state amp will be high enough as to not cause an audible difference in sound.

It could also be the fact that I was once a real musician who played trombone in a brass section. My brain is telling me something is wrong because I know how something is supposed to sound and when it sounds different than expected, it just sounds wrong.
Regardless, I have been involved in clinical trials before, and I am always the unlucky one who experiences something that 95% of the group DOES NOT experience.

The differences you are hearing could very well be "real".....but you are incorrectly attributing to the class of the amplifier instead of the real cause of the difference (which is the result of known, measurable differences in things like power, gain structure, complete differences in setups, etc).

They are not, however, the result of the amplifier class.

 

[loud-n-low 10+ year member]

why did the major majority of people in the early 90's hate the sq of class D amps? undeveloped technology? high thd? Im curious