[Tyson]

Too much negative feedback is bad idea in class AB, better specs but worse sound. Class D is a very different technology, different tricks.

Better a new thread.

Yes, I agree with you.  I like Class D as a concept, once it gets to a point where it's as good as the best tube amps or best SS amps I'll get one to use in my system.  I already have a great tube amp and great SS amp I can rotate in (based on my mood), it'll be good to have a great Class D option as well.  At the moment, however, I haven't heard a Class D amp that is worth owning (for my tastes).  The DAC amps are close, but not quite there yet (for me).  I'll get a chance to hear a Mivera amp in my system pretty soon, maybe it'll close the gap (or maybe it won't).  I will say this, Class D has improved tremendously since I first heard the Hypex/NCore amps (which were straight up sterile sounding).

Will class D merely "catch up" to tubes and Class A(B) SS amps?  Or will it leapfrog over both and re-define what's possible in audio?  I don't know.  We'll see.  So far, it's still playing catch up.

[maty]

The key is the topology and not tubes or SS.

The SE topology (tubes or SS) => H2 predominant => EMOTION.

Preamp with SE topology + very clean class D poweramp (without harmonics) and you have EMOTION + Big SOUNDSTAGE.


Very clean system but without H2/H4 harmonics: Big SOUNDSTAGE but without EMOTION.

[Tyson]

The SE topology (tubes or SS) => H2 predominant => EMOTION.

Preamp with SE topology + very clean class D poweramp (without harmonics) and you have EMOTION + Big SOUNDSTAGE.


Very clean system but without H2/H4 harmonics: Big SOUNDSTAGE but without EMOTION.

Yes I agree removing even order harmonics is generally detrimental to the sound.  But don't you see that your example shows that Class D, even at it's best, is not satisfying.  One needs to put a tube preamp in front of it to get it to sound acceptable.  That's a problem. 

You and I might agree that stripping the even order harmonics is bad, but others will not.  They will say something like "well, the problem is NOT that my Class D topology has stripped the emotion from the music and you need a colored tube preamp to make it sound good.  NO, the REAL problem is that your system isn't transparent ENOUGH!  So take out the colored tube preamp and use a Class D preamp (or even better, no preamp at all), and just color the sound using your DAC!"  Idiotic.  But, people have said it.  Often, and loudly.

[wushuliu]

Code: [Select]

:popcorn:

Thank you sir!

[OzarkTom]

 

Did I wake up and now it is 1964 again? That is what the class d companies were saying when class d first came out. All other amps were obsolete.

I have a good idea, since all AB amps are now obsolete again, send them all here and I will give them an honorable burial here in the Ozarks.

[maty]

Yes I agree removing even order harmonics is generally detrimental to the sound.  But don't you see that your example shows that Class D, even at it's best, is not satisfying.  One needs to put a tube preamp in front of it to get it to sound acceptable.  That's a problem...

Yes, that is the problem... with OLD class D.


Imagine:

First, you have clean power (very important). On mains or after to clean it like me (I have very big problems with mains at home).

DAC

Very clean, almost without measurable jitter. And without harmonics.

Preamplifier

Class A, SE topology, digital volume (chip) or step relay attenuator. Tubes or SS your choice/taste.

Poweramp

Very clean, without harmonics.

Speakers

With very low distorsion -> problem: low sensitivity -> you need watts.


DAC: RME ADI-2 DAC. Digital volume.

Preamplifier: AKSA's Lender Preamp with 40Vpp Output, with less output and with the H2 level you want and the new 64 step relay attenuator designed by JPS64. SE topology and more cheap than others. No need to use hard-to-find transistors as usual with Nelson Pass class A designs. You can build it or entrust it to someone.

Poweramp: IcePower 1200AS2. With good case and cables to avoid RF/EMI interferences.


Now you have the best of ALL technologies in 2018. And without to spend a lot of money if you want to listen very good records with high DR like me.

[macrojack]

Did I wake up and now it is 1964 again? That is what the class d companies were saying when class d first came out. All other amps were obsolete.

I have a good idea, since all AB amps are now obsolete again, send them all here and I will give them an honorable burial here in the Ozarks.

Tom - MEMBERS WILL NEED YOUR ADDRESS. Shipping to you might be cheaper than recycling electronics in some locales. This is also a service that many a triumphant widow might employ. You're thinking outside the box.

[Tyson]

Maty, I have all of those things.  Except low sensitivity speakers.  I have high sensitivity speakers (97db w/flat 8ohm impedance).

I think we're in agreement here.  The only place we differ is with regard to class D ultimate quality as of today.  DAC and their Maraschino amps are the primary reason I think class D has a future in high end audio.  Before I heard them I dismissed class D based on it all sounding a bit airless and sterile.  DAC made me reconsider that opinion.  Will others be able to replicate their success?  Maybe.  I hope so.  I hope it continues to improve by leaps and bounds.  But I've been in this game long enough to be skeptical of "game changers".  I'll believe it when I personally experience it.  That hasn't happened so far....

[macrojack]

Unlike Class A/AB, class D enjoys the advantage of being able to subsidize hi-end R&D by selling gazillions of small, cheap consumer level Class D amplifiers. Not something likely to proceed from the business models of our revered former all-star amp providers.
BTW - It's probably been 10 years since I bought my first Class D amplifier from Jeff Rowland. So the established amp manufacturers have not all been sleeping.

[wushuliu]

Maty, I have all of those things.  Except low sensitivity speakers.  I have high sensitivity speakers (97db w/flat 8ohm impedance).

I think we're in agreement here.  The only place we differ is with regard to class D ultimate quality as of today.  DAC and their Maraschino amps are the primary reason I think class D has a future in high end audio.  Before I heard them I dismissed class D based on it all sounding a bit airless and sterile.  DAC made me reconsider that opinion.  Will others be able to replicate their success?  Maybe.  I hope so.  I hope it continues to improve by leaps and bounds.  But I've been in this game long enough to be skeptical of "game changers".  I'll believe it when I personally experience it.  That hasn't happened so far....

The airless and sterile Class D is not anything I've heard for a while. But then I play around with diy a lot. I don't know how anyone can call TI's TPA series sterile, or even the older and more finicky IR2092. TI has been catering to the diy crowd recently with half off their eval modules. Just add a PS and judge for yourself for peanuts (in audiophile terms). To me they sound like the best of tube and solid state combined.

[OzarkTom]

It is also OK to send all those poor speced Tube amps. I always loved the looks and sound of the Bel Canto tube amps, then they switched to the better speced class d amps and they lost me. I would love to have someone send me one of those.

[maty]

The game here is that you no longer have to change poweramp every time you get tired of the sound.

You can modify it via DSP from the RME DAC (or equivalent) or from software player (64 bits if possible, like me with J River MC). Or change the preamp or modify the H2 level of the AKSA.

The last Maraschino poweramps have very good specs too (and very good engineering I think). Few less SNR but more bandwith than 1200AS2 (it is an engineering compromise). They are more expensive.

[Tyson]

maty, the problem with your proposal is that it assumes a class D amp doesn't have a sound.  Which is not true.  Every piece of audio equipment has a sound, none of them are truly transparent. 

The game here is that you no longer have to change poweramp every time you get tired of the sound.

You can modify it via DSP from the RME DAC (or equivalent) or from software player (64 bits if possible, like me with J River MC). Or change the preamp or modify the H2 level of the AKSA.

This is true for any amp, not just Class D amps.

My disagreement with you is not that one shouldn't make changes to the D/A converter (or playback software) or that you can't adapt the sound via your preamp choices.  Those are things that are true no matter what amp you have.

No, my skepticism is your claim that class D amps are fully transparent and have no sound of their own.  Maybe true, maybe not.  We'll see. 

[maty]

The more important question is: Do you get excited when listening to some excellent recordings?

I have listened to systems / rooms where the music sounds spectacular (with or without room equalization) with the owner's recordings. Then I put mine and they sounded bad. That if they were old, if that was only in mono .... Spectacular yes, EMOTION not.


By the way, imagine speakers with low distorsion with very good coaxial or tweeter with logarithmic waveguide: more SOUNDSTAGE again.

[Tyson]

The more important question is: Do you get excited when listening to some excellent recordings?

I do, using my nice tube amp.

I have listened to systems / rooms where the music sounds spectacular (with or without room equalization) with the owner's recordings. Then I put mine and they sounded bad. That if they were old, if that was only in mono .... Spectacular yes, EMOTION not.

I feel that way about most SS and all class D up to this point - impressive but not emotionally engaging.

By the way, imagine speakers with low distorsion with very good coaxial or tweeter with logarithmic waveguide: more SOUNDSTAGE again.

That's the Geddes approach to speakers, which is very good.  Or you could use planar-magnetic drivers in an MTM open-baffle configuration with a quad set of open-baffle servo controlled self-powered subwoofers on the bottom.  That's what I have and it's pretty awesome. 

Well done open-baffle speakers have a larger, more realistic soundstage than any box speaker I've ever encountered.  That's not hugely important on Rock/Pop/Jazz recordings, but it's very important on large orchestral classical recordings (or any classical recording, really).  Since I'm 90% classical for my listening, well there's no box speaker that can touch OB speakers for a massive sense of scale.  Except maybe a line array.  Yeah, line arrays are pretty awesome too, wish I had space for one. 

So yeah, to answer your question, I do in fact get excited to listen to music on my system and it sounds not just spectacular, but emotionally engaging as well.  I have a great tube amp literally sitting on top of a great SS amp in my system and I can swap them in and out at will.  IME, even great SS amps aren't as emotionally engaging as great tube amps. 

[maty]

Orchestral music with open baffles + big sealed subwoofers sounds INCREDIBLE. But the other music sounds worse 

Someone only listen the sound, others the music.

Just now, again:

J. S. Bach, Concerto Köln ‎– Brandenburgische Konzerte (2018), vinyl

https://www.audiocircle.com/index.php?topic=68964.msg1683714#msg1683714

Great sound, music and interpretation but without emotion. Digital master -> clean sound but...

If you get excited do not spend money in other hard!

[Tyson]

Orchestral music with open baffles + big seales wubwoofers sounds INCREDIBLE. But the other music sounds worse 

I dunno, I was listening to the remaster of Nirvana's "Nevermind" the other day and it sounded freaking amazing.  That kick drum, the wailing guitars, the raging vocals, it all sounded massive, propulsive, and hugely emotionally engaging.

I do agree that OB speakers often sound weak on Rock/Pop (and some jazz) because of weak upper/mid bass.  Which results in a "musical" but not "punchy/propulsive" type sound. 

Which is why I am so impressed with the quadruple 12" servo subwoofer bass system that Danny at GR research came up with.  It solves the biggest weakness in OB speakers quite elegantly - strong, punchy bass. 

Mahler, Beethoven, Bruckner, Tool, Nirvana, The White Stripes, Tom Waits, Ella Fitzgerald, Billie Holiday - all of them sound amazing. 

But, to get back to the original topic of this thread - OB speakers measure worse than box speakers (generally speaking).  Tube amps measure worse than SS amps (or class D amps) generally speaking, and many of the recordings I listen to are not audiophile quality by any stretch.  Which is why measurements are so deceptive.  There's no measurement that can track emotional satisfaction. 

So if Stereophile keeps publishing measurement, or not, it's kind of irrelevant.  The only real way to find out if something sounds good is to actually listen to it, in your own system, over a period of several weeks.  Everything else is just guessing or speculation. 

[Jonathon Janusz]

They will say something like "well, the problem is NOT that my Class D topology has stripped the emotion from the music and you need a colored tube preamp to make it sound good.  NO, the REAL problem is that your system isn't transparent ENOUGH!  So take out the colored tube preamp and use a Class D preamp (or even better, no preamp at all), and just color the sound using your DAC!"  Idiotic.  But, people have said it.  Often, and loudly.

Somebody call the cops.  I think I just saw shots fired. 

[JohnR]

Unlike Class A/AB, class D enjoys the advantage of being able to subsidize hi-end R&D by selling gazillions of small, cheap consumer level Class D amplifiers.

That's a good point.

[maty]

Posts ago, Tyson mentioned the negative feedback in traditional amps (class A and class AB).

Today, Hugh Dean (AKSA) write about it and the phase.

http://www.diyaudio.com/forums/solid-state/318102-aksa-lender-mos-hybrid-aleph-alpha-amplifier-post5422743.html

I think it is very instructive.