Perhaps it depends on what kind of class D amp.
There's the normal one that presents as any other amplifier - analog inputs are transformed into a time varying PWM. Then there's the kind that combine DAC and PWM within the same silicon - digital inputs are transformed into a time varying PWM.
I think I can hear such "tizzy, grainy, distorted, whatever that sound is subjectively" from DACs themselves and understand it's possible to get a good one that doesnt do that. Likewise, I'd extend that it's possible to get a good direct conversion from digital to amplifier power output in class D.
If within different chips / architectures comprising DACs, some sound better than others, I'd imagine the same could be said for various Digital to Power Analog Converters, with a typical design using a class D output, like a 1-bit DAC.
Almost like saying "anyone have an experience with a tube amp sounding bad?" Yeah.
There's the normal one that presents as any other amplifier - analog inputs are transformed into a time varying PWM. Then there's the kind that combine DAC and PWM within the same silicon - digital inputs are transformed into a time varying PWM.
I think I can hear such "tizzy, grainy, distorted, whatever that sound is subjectively" from DACs themselves and understand it's possible to get a good one that doesnt do that. Likewise, I'd extend that it's possible to get a good direct conversion from digital to amplifier power output in class D.
If within different chips / architectures comprising DACs, some sound better than others, I'd imagine the same could be said for various Digital to Power Analog Converters, with a typical design using a class D output, like a 1-bit DAC.
Almost like saying "anyone have an experience with a tube amp sounding bad?" Yeah.
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The Devaliet is a current dumping oddidy. I would not tar all classs D based on that.
having trouble not lumping this with 'silver cables sound bright'. The same stuff gets repeated by all who don't like them.
That is why I was careful to say IME. Obviously, I can't have experience with every class D amp ever made. Its was simply a summary of my opinion based on experience to date. Also, I was responding to a question asking about personal experience.
Regarding silver cables, no personal opinion, haven't tried them.
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The speakers themselves are pretty good. They would probably make great PA speakers for a small club.
The Crown class D amps that JBL approved for use with the speakers are bad (for hi fi, to me). A former JBL speaker engineer Jam contacted through a mutual acquaintance told us the same thing: Get rid of the Crown amps and build an analog crossover of some kind if best sound quality is wanted. He said that's what he would do. Of course, we didn't need him to tell us what was already obvious from listening. He did have some good suggestions about how to start out if a passive crossover design was wanted.
Somewhere I may still have the link to a long website article written by a guy who redid the digital crossover for his M2 speakers in HQ Player, with them being calculated at high resolution and run through a better dac than the one inside the Crown amps. That's probably a good way to go with M2s for hi fi, assuming one's dac is good enough.
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There's a substantial difference between these two.
Maybe the newfangled ADC-upsample-to-1-bit is called Class D in "Teh Literature" but I hesitate to call it that, there's too many differences. It's basically standard digital converted to DSD.
Your friend 31697B (formerly known as RN Marsh) would disagree with you on that. M2s are his reference speakers. https://www.diyaudio.com/forums/the...wtorch-preamplifier-iii-3279.html#post6020286
DAC hasn't been a bottleneck in audio electronics since late 90's.
A digital crossover (assuming digial source material) with a bi- or tri- amping will be better than an analogue power crossover. More accurate, no power inductors needed, etc.
Have you ever heard them? In a blind comparison ( dont start with your blind BS) trained listeners had trouble deciding which was better, M2s or more expensive Revels, the big Salons I believe. Guess who Im believing.
Theoretically, sure.
I don't know if its possible to get a dac today that doesn't do that stuff to some small yet slightly audible extent.
With class D amps its getting bit more interesting since Bruno Putzeys started talking about a type of memory-effect-IMD from hysteresis in the iron core output inductor. Now that he has a class D amp that switches fast enough to get by with an air core inductor he is talking about it. His partner at Purefi still thinks there may be some other memory effects they haven't found yet. My guess is he thinks that because even with an air core inductor he still hears some things he can't account for with sine wave measurements. Just a guess though.
The M2s are at my house right now. The big Sound Lab electrostats also here kill the M2s (slight exaggeration, but I don't want to overuse the word 'better'). That's with the M2s on analog power amps. Using the Crown class D amps it isn't even a fair fight, the M2s lose badly.
Note: Very possible the JBL M2-approved Crown amps Richard ended up with aren't the finest sounding class D amps Crown ever made. They are I-Tech 5000, original version.
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So a mate of a mate of a mate reckons analog crossovers are best? You'll have to excuse me not taking that particularly seriously.
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There is more to the story. The former JBL engineer worked with the same JBL drivers (used in M2) for another speaker project using passive crossovers. He provided us with his measurements and preliminary crossover design. Thanks to him, I have a whole cache of info on M2s.
To amplify this point: there is always a DAC in the chain, because all sources are digital. (Except perhaps in some British hold outs
So it just makes sense to do all the filtering in the digital domain, for the reasons indicated by Gpauk, and then have quality DAC's for each speaker driver.
So? How does that prove anything OTHER than he worked out a passive crossover scheme? Doesn't add any evidence to the debate on active vs passive.
To amplify this point: there is always a DAC in the chain, because all sources are digital. (Except perhaps in some British hold outs
Oh, true. However the JBL engineer was a US phono holdout. He's probably right that if one starts in the analog domain, best to stay there. Jam agrees, he is another holdout. Myself, I like the one dac channel per driver approach. Just make it a good dac, and a good power amp, please
Of course, not a phono user myself...
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