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Discussion of Class D Amps Application & Experiences

With all the time off that our current situation has allowed recently, I became intrigued by the idea of class D amplification. I have always been against this type of amplifier but the more I have read the more I have also learned. There are lots of threads here on this subject many of which result in arguments about which amplifier class is better. I do not want to do that here. As I consider a class D amp I need to let you know that I currently use a fairly powerful class A/B SS amp and pre-amp into an efficient pair of speakers rated at 4 ohms. My choice of equipment has always been focused on musicality over absolute detail. I want the music to sound natural and not sterile. I seem to have achieved that sound. If I switched to class D amplification that would also be my intended goal although a bit more refined detail would be fine. I have considered pairing the amp with a tube pre to help achieve my desired sound. So why would I change? My goal would be to save money over my current gear while maintaining my desired sound.

I have researched brands such as Nord, Primare, AGD & Nuprime. I have also looked at brands such as Jeff Rowland & Merrill but those are way out of my price range. My target would be $6000 - $7000 or less. I'm about performance not price. So given that background information I would like to hear from those who have made the leap, what your experience has been (likes and dislikes), what amp did you replace and any comments about one brand over the other. Your experience with demos etc. Do you use a tube or SS line stage?
Thanks
falconquest
atmasphere's avatar
atmasphere
12,421 posts
 
So, based on your response would you say this a 10% improvement? 20%?
Hard to say in that regard! If properly engineered, its probably not that big a deal, as MOSFETs have gotten faster in the last few years since the GaNFETs were introduced. @arion  makes extremely good points in his post; this reflects my own experience. Some class D amps are extremely boring, some are bass shy (usually older units) and others sound extremely musical (mostly newer units).
mapman's avatar
mapman
23,620 posts
 
Some class D amps are extremely boring, some are bass shy (usually older units) and others sound extremely musical (mostly newer units).

Of course the same could be said about any amp design type in general.

That’s why it’s best to not generalize. No two amps of any particular type are created equal. They all run the gamut.

Point is Class D CAN compete. That’s all.

Also I agree newer in general is better than older as is the case always with any newer and still more evolving technology. Also cost is NOT necessarily the best determining factor as usual. Even my tiny $75 Fosi Class D amp (about the size of a pack of cigarettes) with its tiny Texas Instruments Class D chip competes very well with anything else I have heard ever up for up to a few hundred dollars and will beat most vintage amps that sold for 2-5X more 40 years ago in a package 1/10th the size and the Bluetooth even works well enough for most if not the most critical 2-channel applications.

That’s how technology and progress works!

Can you believe we still use the same primitive disk-groove-based-like-riding-a-roller-coaster approach for records and playing them that was first invented well over 100 years ago? What’s up with that?

Try singing or playing a violin while riding a roller coaster sometime.

falconquest's avatar
falconquest OP
1,109 posts
 
" That’s why it’s best to not generalize. No two amps of any particular type are created equal. They all run the gamut."

This is why I would like to hear from those who made the leap from class A, A/B to D to get their impressions about not only the sound but what sounds better or worse after the transition. Did they find equal or better performance for less money or were there trade-offs? I was also thinking along the lines of a tube pre but it seems hard to find one that offers a remote and no quirky aspects. (I researched the Conrad Johnson 17LS but didn't like the idea of the "click" volume control.) But I don't want to make this about pre-amps.....yet.
djones51
4,947 posts
 
I wouldn't worry to much about the op amp the stock TI LM 4562 will measure right there with any discrete sparkos or sonic imagery. The newer iterations of Class D show better bench numbers but when you start getting into harmonic distortion numbers <-100 you're not going to be able to tell any difference anyway. Adding tubes to Class D amps seems self defeating to me you're adding distortion to an amp made for neutrality. The best at giving great detail without fatigue I have heard are amps with Purifi but Hypex is very close I haven't heard  ICE amps so they could be better though the few  measurements  I have seen on them aren't as good.
mapman's avatar
mapman
23,620 posts
 
I had the ARC sp16 prior to the Class D amp and have had that combo for ~10 years now and still content. Next pre-amp will probably be SS. Maybe a Benchmark pre/DAC device is what I am thinking currently. 

Arc sp16 has a nice basic function remote.
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