Audiophiles, generally don't like class D amps!

[mhardy6647]

Speaking of Class D amplifiers...
I was looking for something else entirely* today on WRH and I stumbled across what, at a very (!) quick glance, looks like an interesting discussion of the various classis of amplifier topologies (yes, including D) published way back in 1989 in a periodical called Studio Sound.

This is the first page of Part 3 of the three-part series.

If this trip down amplifier memory lane is of any interest, the three parts may be found in these three issues of Studio Sound.

https://worldradiohistory.com/Archive-All-Audio/Archive-Studio-Sound/80s/Studio-Sound-1988-12.pdf (pg. 60)
https://worldradiohistory.com/Archive-All-Audio/Archive-Studio-Sound/80s/Studio-Sound-1989-01.pdf (pg. 43)
https://worldradiohistory.com/Archive-All-Audio/Archive-Studio-Sound/80s/Studio-Sound-1989-02.pdf (pg. 51, but see pg. 81 of the PDF due to a frameshift error )

 

[fpitas]

Speaking of Class D amplifiers...
I was looking for something else entirely* today on WRH and I stumbled across what, at a very (!) quick glance, looks like an interesting discussion of the various classis of amplifier topologies (yes, including D) published way back in 1989 in a periodical called Studio Sound.

This is the first page of Part 3 of the three-part series.
View attachment 270994

If this trip down amplifier memory lane is of any interest, the three parts may be found in these three issues of Studio Sound.

https://worldradiohistory.com/Archive-All-Audio/Archive-Studio-Sound/80s/Studio-Sound-1988-12.pdf (pg. 60)
https://worldradiohistory.com/Archive-All-Audio/Archive-Studio-Sound/80s/Studio-Sound-1989-01.pdf (pg. 43)
https://worldradiohistory.com/Archive-All-Audio/Archive-Studio-Sound/80s/Studio-Sound-1989-02.pdf (pg. 51, but see pg. 81 of the PDF due to a frameshift error )

Someday that class D will take the world by storm!

 

[ModDIY]

Someday that class D will take the world by storm!

It's already started.

 

[fpitas]

It's already started.

But only for digital music

 

[mhardy6647]

But only for digital music

Of course.
That's what the D stands for...

 

[Mart68]

Audiophile Glossary:

Class A - 'A' is the first letter of the alphabet so it's the best. Like getting an 'A' in an exam or flying first class. Expensive but better

C;lass AB - Like flying business class. Not quite as good as first class but most of the advantages without the extra expense

Class B - Coach

Class D - 'D' is for 'Different' or 'Digital' - it gets you there but it's not the same. Like getting the train instead of flying or listening to a CD instead of a first pressing.

Class G/H - don't know what they do but look how far down the alphabet those letters are. Can't be any good no matter what.

 

[fpitas]

Audiophile Glossary:

Class A - 'A' is the first letter of the alphabet so it's the best. Like getting an 'A' in an exam or flying first class. Expensive but better

C;lass AB - Like flying business class. Not quite as good as first class but most of the advantages without the extra expense

Class B - Coach

Class D - 'D' is for 'Different' or 'Digital' - it gets you there but it's not the same. Like getting the train instead of flying or listening to a CD instead of a first pressing.

Class G/H - don't know what they do but look how far down the alphabet those letters are. Can't be any good no matter what.

Class C is just average.

 

[Deleted member 48726]

I don't like class D. I want my heavy old school A/B heaters with dusins of transistors.

 

[fpitas]

I don't like class D. I want my heavy old school A/B heaters with dusins of transistors.

That may be coming, like the preamps with superfluous tubes you can get now. Class D amp with lots of transistors that do nothing but get warm, and some sheet steel to weigh it down for old times sake.

 

[Galliardist]

My Marantz is nearly there: Hypex, but got the heavy case and an old school preamp section, still barely gets warm though

 

[symphara]

It seems to me that if you've built a system out of a bunch of idiosyncratic components, each of which attempts to compensate for the deficiencies of the others, replacing an inaccurate component with a strictly accurate, uncolored component is as likely to harm the perceived sound as it is to help it. So it may be the case that when people audition these amps, they hear things they dislike that originate elsewhere in the chain? Or maybe it is mostly confirmation bias.

Anyway, this seems like the problem with a purely subjective approach -- not building upon a foundation of measured accuracy is likely to lead to neurotic whack-a-mole behavior as you grope your way through the audio chain seeking improvements. It's great for the high-end audio industry because their customers keep coming back, but it seems like kind of a silly hobby. I have no problem paying for luxurious, cool-looking casework -- that's art! -- but I don't want to spend my life on a quixotic quest for audio bliss with no understanding of the fundamentals.

This sounds great - building the system the opposite way - until you realize that:

(1) most things you can buy aren't measured at all; therefore if you limit yourself to what's measured and then in particular what measures well, you're stuck with a handful of products that might be out of your budget, out of your reach (no dealers), out of your skill window to operate (rPi, DYI amp kits etc) or that you plainly don't like.
(2) the most important things in the reproduction stage are your speakers and your room, and both are the messiest, non-linear things; so perhaps it's more important to look for synergies and equipment features that can help with that (EQ) rather than maximizing the "measured accuracy" of your DAC or amp.
(3) that ultimately this is something personal and not a case of one-size-fits-all, and you can optimize all you want for measurements and won't be any guarantee that you'll enjoy the end result

Not to be interpreted that I like what you [correctly] describe as "whack-a-mole". The problem is that the existing scientific approach is, in my personal opinion, in its infancy and not that helpful.

And by the way, I love my class D 1120 Lyngdorf. So much so that lately I've been considering swapping my big AB amp for a TDAI-3400.

Primare though I don't - I tried A34.2 - very powerful but obvious shrill sax.

 

[Porter]

I might get crucified for it here, but I'm one of the people who doesn't particularly jive with the sound signature of some Class D amps, specifically in the treble. I don't know if it's the different presentation of harmonics or what exactly, but it is very fatiguing to my ear over time.

I have several thousand hours of listening on my NAD M10 on several different types of speakers, both direct (unadjusted) output and also tweaked via Dirac. It's slightly better with Dirac but the lingering high frequency difference is still there. Current speakers are Klipsch Heresy IV, so it's not a "difficult load" problem.

When I started using the pre-outs to a Schiit Vidar (class AB) it improved dramatically. Fatigue dropped immensely and now I don't notice it at all. Seems like an utterly unnecessary thing to need to do, though. If the Hypex nCore in the M10 is even remotely what they claim it to be, it should be almost entirely transparent, and I don't find that to be true in practice.

If anyone has an opinion on this, please share. I'm all ears (pun intended).

 

[NiagaraPete]

I've never listened to a class D amp. My Genelec's have class AB, all my previous amps have been AB. One amp that sort of tweaks my interest is the Topping LA90 but it's AB as well.

 

[valerianf]

Amir tested the NAD M10 analog input with a low gain of 7.2 dB only and noticed some noise issue.
@Porter did you used the analog input?
The Klipsch Heresy IV has a large 30cm woofer that imply a large inductance/capacitance seen at the output of the class D amp.
Another ASR forum thread initiated by @pma investigated the fact that the high audio range THD+noise is seriously impacted when the class D amp is connected to a large complex load.
https://www.audiosciencereview.com/...ments-into-4ohm-2-2uf-load.43162/post-1546910
Is it possible that it is what happened with the Klipsch Heresy IV?
A quick test could be using the bi-wiring speaker connection (! remove the jumpers) and placing the class A/B on one binding and using the class D for the other one.
My guess is that the best sound quality will be with class A/B connected to the mid-range and tweeter.

 

[Andysu]

behringer is regular class d

 

[NoxMorbis]

Ok, I know I shouldn't, but I've been reading feed back on an audiophile site on experiences with various Class D based amplifiers. (Purifi, Ncore, and a couple of others less well known to me)

I expected a bit of bias towards older technologies, but it was close to 100% against class D.

What is it that these people are experiencing? They can't all be wrong can they?

• Is it that they miss the distortion/colour from their class AB amps?
• Has this become normalized/expected?
• Have they been programmed to dislike class D because everyone says it isn't as good, i.e bias?
• Is there actually something else at play here?

Everything I hold as important in audio and electronics in general is about achieving the required performance/specs, 'the truth', or at least as close as we can economically get, am i wrong, because these people would appear to say so.

It sounds as if you have mistakenly visited the audiofool forum, not the audiophile.

 

[Purité Audio]

I might get crucified for it here, but I'm one of the people who doesn't particularly jive with the sound signature of some Class D amps, specifically in the treble. I don't know if it's the different presentation of harmonics or what exactly, but it is very fatiguing to my ear over time.

I have several thousand hours of listening on my NAD M10 on several different types of speakers, both direct (unadjusted) output and also tweaked via Dirac. It's slightly better with Dirac but the lingering high frequency difference is still there. Current speakers are Klipsch Heresy IV, so it's not a "difficult load" problem.

When I started using the pre-outs to a Schiit Vidar (class AB) it improved dramatically. Fatigue dropped immensely and now I don't notice it at all. Seems like an utterly unnecessary thing to need to do, though. If the Hypex nCore in the M10 is even remotely what they claim it to be, it should be almost entirely transparent, and I don't find that to be true in practice.

If anyone has an opinion on this, please share. I'm all ears (pun intended).

I might look at your choice of loudspeaker re the treble issue,

Klipsch Heresy IV Review (Redux!)

Klipsch Heresy IV Review

www.erinsaudiocorner.com

Keith

 

[roog]

It sounds as if you have mistakenly visited the audiofool forum, not the audiophile.

I don't see any benefit from using demeaning labels for people who have strong belief systems, it is my hope that a greater number of people will learn and understand why their stereo does what it does based on science and that they hear what they want to hear due to psychology.

Long may we banish the charlatans that market nonsense and the easiest way to stop this is for people not to buy their stuff. If companies start to realise that the truth and perfected products sell, they might actually join the program and improve the stock. Its a big ask I know!

Surely the world must be a better place when we have more understanding, fingers crossed anyway.

Enjoy your listening and of course your science :0)

 

[roog]

I might look at your choice of loudspeaker re the treble issue,

Klipsch Heresy IV Review (Redux!)

Klipsch Heresy IV Review

www.erinsaudiocorner.com

Keith

Sadly, I believe you are right Keith, back in 2017 or was it 2018? before I knew of this place I spent several hours at my dealer listening to version III of this speaker, I wanted to like them, they look impressive, the sound was initially impressive, but I realised that even with my 50+ year old hearing I would not be taking them home to stay.

*Edit, sorry I have just realised I was listening to the Forte III but, I suspect they have a similar sound signature in the treble.*

 

[Purité Audio]

All the Klipsch models I have heard have a ( vastly) up tilted treble, long term I find that intolerable, but only my personal opinion.
Keith