Audiophiles, generally don't like class D amps!

[voodooless]

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).

Typical classist comments.

Both the Vidar and the M10 have a flat enough frequency response and in fact the M10 is about half a dB down at 20 kHz compared to the Vidar. They both have rising distortion with frequency, SINAD wise they are very comparable, although the M10 will do better at high levels and the distortion products are some 10 dB lower. High-frequency distortion is also probably a bit better. Overall, they should be very similar performance wise, probably giving the edge to the M10. Which one is more transparent? The M10, maybe by a hair?

I bet you’ve never done a properly level matched comparison? I doubt you could keep them apart.

 

[SIY]

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).

Not crucified, but we'd STRONGLY suggest you do a listening test ears-only, basic controls. Double blind, level-matched. Peeking can lead to all sorts of errors.

 

[roog]

Guys, I'm new here and wanted to know, is there an app for IOS (to use on iphone) to understand how right the mid, hi and bass line is? I'm looking to understand how well the music is set in my car.

Sorry I can't help you but it might be better (greater visibility) if you make a new thread with that as the topic.

 

[Bjorn]

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).

One needs to remember that an amp with low distortion is revealing of flaws in speakers, acoustics and the recording. I'm not really surprised by your experience with the speakers you have. Sometimes what we perceive as issues in the treble migh actually be in the midrange BTW.

Klipsch Heresy IV Review (Redux!)

Klipsch Heresy IV Review

www.erinsaudiocorner.com

 

[Waxx]

Some may qualify me as an audiophile (because l like tube amps and other amps with high harmonic distortion and single driver fullrange speakers), and i was a longtime critic of class D amps and smps for audio, but both technologies became mature and on a quality level that even i like them, even without the beloved harmonic distortions.

I have a Hypex NCore amp, i have also a cheap class D SMSL SA-36, and even that cheap amp is quiet decent today and miles better than most class D amps of 10 years ago (all except NCore actually). And a well build smps is actually better in most cases than a linear psu today and even used in high voltage tube gear like some of the devices (studio and hifi) of Manley Labs. Those cliché's that run arround in so called "audiophile" circles are based on the devices that were build before the tech became mature and are not valid anymore with most new devices, because tech moved on and solved those issues.

But i still got my tube and class A amps also, whatever they say here, and i still love and use them daily. And if you prefer the sound those old technologies like i do, you should keep them also. But saying that class D or smps psu's are not cleaner and more hifi in the traditional sense of the word (high fidelity aka no colouration or distortion) than the old tech is bullshit, proven more than once on this site and many others.

 

[DavidEdwinAston]

Groupthink.

Steady on keiron, don't we proudly have group think?.
Backed up by science!

 

[fpitas]

Steady on keiron, don't we proudly have group think?.
Backed up by science!

It's an interesting philosophical point. If your opinions are backed up by valid proof, is group-think the applicable term?

/Proud "Round Earther"

 

[DavidEdwinAston]

Po

It's an interesting philosophical point. If your opinions are backed up by valid proof, is group-think the applicable term?

/Proud "Round Earther"

Possibly, possibly not fpitas!
Hmm, Round Earther may be political.
So, Proud anti brexiteer!

 

[fpitas]

Po

Possibly, possibly not fpitas!
Hmm, Round Earther may be political.
So, Proud anti brexiteer!

Yes, in some quarters believing in a round Earth is very closed-minded

 

[MaxBuck]

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).

Some people seek sound reproduction that favors "pleasant" over accurate. Nothing wrong with that. Sounds like you want less treble than the recording engineers generate.

 

[mhardy6647]

Hyperspherical Earth FTW.

 

[Porter]

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.

I'm not sure the Klipsch is that complex a load. It's certainly treble forward, but I'm ok with that part, particularly when coupled with the ability to adjust the freq response a bit with Dirac. I've tried it in a bi-wire configuration as well, both with the M10 driving the upper half of the speaker (with a class AB driving the large midbass driver), and in reverse, with the M10 driving the midbass driver and alternative amps driving the upper half of the speaker. The latter was just easier to live with, for me.

I've also run the M10 with other speakers, including some that are definitely not treble-forward at all, so this isn't just a Klipsch thing.

Generally, what I find is that the M10 sounds great in any of these configurations, there's no directly audible grain or difference due to being Class D, I agree that people making those claims are mostly self-deluding based on their expectations. In fact the audio level of the Schiit Vidar is almost identical to the M10's internal amp, which was surprising to me, usually you have some volume matching to do, but in this case they are really, really close. But my experience of listening over long periods does indicate a qualitative difference of some kind to me, particularly with mixed material, as in casual use my wife and I switch between streaming TV audio, streaming lossless music, analog sources like a turntable, etc. There is something experientially different about the treble when using the M10's internal amp, and I don't know if that's a particular interaction of the DAC/preamp in the M10 when coupled with its amplification, or if it's something specific to the amp section itself.

 

[Porter]

Some people seek sound reproduction that favors "pleasant" over accurate. Nothing wrong with that. Sounds like you want less treble than the recording engineers generate.

I am not sure, it's difficult to quantify what "accurate" means when more than one amp used have plenty of treble extension and measurably flat frequency response well above the limit of human hearing, and sound near-identical to one another when listening casually or even very intentionally, yet have a different effect on the overall impression and engagement with music over time. It's difficult to quantify that, and the only thing I see that's different in the measurements in the Hypex amp in the M10 is rising THD over the freq range when tested... is that sub-audible but affecting to the listener? I think it's hard to say. I certainly don't know if that's the relevant bit or not, I have no idea.

 

[voodooless]

the only thing I see that's different in the measurements in the Hypex amp in the M10 is rising THD over the freq range when tested...

The other amp has a similar THD rise with frequency.

 

[Porter]

Typical classist comments.

Both the Vidar and the M10 have a flat enough frequency response and in fact the M10 is about half a dB down at 20 kHz compared to the Vidar. They both have rising distortion with frequency, SINAD wise they are very comparable, although the M10 will do better at high levels and the distortion products are some 10 dB lower. High-frequency distortion is also probably a bit better. Overall, they should be very similar performance wise, probably giving the edge to the M10. Which one is more transparent? The M10, maybe by a hair?

I bet you’ve never done a properly level matched comparison? I doubt you could keep them apart.

I'm sorry... "classist"? I'm really struggling to understand what you mean.

I have not claimed that I can "hear a difference" between the two amps. On the contrary, I think they sound remarkably similar. There's absolutely no way I could tell them apart in a cursory blind A/B test. The only thing I am talking about is auditory (or maybe sensory?) fatigue over time, which is not a thing that you can detect at all in a short A/B test, whether blind or otherwise.

I can't imagine that I am uniquely or unusually sensitive as a listener, and I've tried a bunch of different amp combinations before beginning to come to this conclusion. I spent a lot of my own money on this NAD unit, and I still use it in my system, so I'm certainly not ideologically driven here. On the contrary, I should be looking for confirmation bias about the brilliance of my gear choices, but I find myself in the opposite situation.

 

[voodooless]

I have not claimed that I can "hear a difference" between the two amps.

Yes you have:

It's slightly better with Dirac but the lingering high frequency difference is still there.

The only thing I am talking about is auditory (or maybe sensory?) fatigue over time, which is not a thing that you can detect at all in a short A/B test, whether blind or otherwise.

How does that even work? You can’t hear a difference but a difference will accumulate over time?

 

[Porter]

One needs to remember that an amp with low distortion is revealing of flaws in speakers, acoustics and the recording. I'm not really surprised by your experience with the speakers you have. Sometimes what we perceive as issues in the treble migh actually be in the midrange BTW.

Klipsch Heresy IV Review (Redux!)

Klipsch Heresy IV Review

www.erinsaudiocorner.com

You certainly could be on to something... but on the flip side, why would this issue be particularly apparent with the M10 alone, compared to the other amps I've tried? FYI that list includes a Schiit Vidar, a B&K Components ST-202, a Denon PMA-2000 mkIV R integrated (in direct amp mode), a Carver TFM-6CB, and a Rotel RB-06. In my opinion the best sound of that list by far was the B&K Components ST-202, it really makes the Heresy IVs sound great and fills in a bunch of lower midrange that the others don't seem to push in the same way. 2nd (but close) behind the B&K were the Rotel and the vintage Carver.

Maybe as you've said, there's a load problem with the Klipsch themselves, but if that's the case, is it not a shortcoming of the amps that some drive it fine and others don't do as well? It's not like these are big 84db efficiency monsters, they're a relatively efficient speaker. Plus, one of the big value propositions with modern Class D like the Hypex nCore was that it's load-invariant and capable of driving difficult speakers without issue, so is there a specific technical reason why it wouldn't be better at controlling a complex speaker load like this, rather than the opposite? I don't know enough about the issue, and would love it if someone could unpack that a bit for me.

 

[Porter]

Yes you have:



How does that even work? You can’t hear a difference but a difference will accumulate over time?

I'm talking about months of leaving it alone and using it casually, without thinking too much about equipment. You develop a general impression of the sound as a sum of experiences. This is not a thing where I'm testing the equipment in an A/B way, instead I'm owning the gear and using it with a bunch of different kinds of material as part of my normal, casual, daily life.

Sure, maybe the general difference in experience is down to a difference in the resolving capability of the amp, i.e. the Class D is actually better in that regard and what I'm hearing is the detail of poorly mastered recordings being revealed, or phase problems in poorly downmixed surround content delivered as LPCM 2 channel from HD streaming services. But that flies in the face of the claim (often used here) that states that all amplifiers that test equivalently will sound indistinguishable from one another unless they are broken. The fact that I don't get the same sonic impression from the other amps over time does tell me something. Sure, maybe that thing is that I'm deluded, and there's nothing sonic that can be perceived or understood as qualitatively different by a human being in audio reproduction at all, and the only thing that matters in the world is a bench measurement. I just don't particularly think that's true, or at all useful as a rigid, reflexive principle.

 

[Waxx]

You certainly could be on to something... but on the flip side, why would this issue be particularly apparent with the M10 alone, compared to the other amps I've tried? FYI that list includes a Schiit Vidar, a B&K Components ST-202, a Denon PMA-2000 mkIV R integrated (in direct amp mode), a Carver TFM-6CB, and a Rotel RB-06. In my opinion the best sound of that list by far was the B&K Components ST-202, it really makes the Heresy IVs sound great and fills in a bunch of lower midrange that the others don't seem to push in the same way. 2nd (but close) behind the B&K were the Rotel and the vintage Carver.

Maybe as you've said, there's a load problem with the Klipsch themselves, but if that's the case, is it not a shortcoming of the amps that some drive it fine and others don't do as well? It's not like these are big 84db efficiency monsters, they're a relatively efficient speaker. Plus, one of the big value propositions with modern Class D like the Hypex nCore was that it's load-invariant and capable of driving difficult speakers without issue, so is there a specific technical reason why it wouldn't be better at controlling a complex speaker load like this, rather than the opposite? I don't know enough about the issue, and would love it if someone could unpack that a bit for me.

I've recently powered a pair of Kiplischhorns AK6's with my Audiophonic build Hypex NCore MC252MP amp (to demonstrate to the friend who owns them). And altought these are notorious for being hard for the amp (due to the ragged impendance) this amp did not have any issues with it at all. It drove it much better than the Bryston 4B (that is much more powerfull) the owner was using with it we all agreed, even in that sense that the owner ordered a pair of Audiophonics NCore mono amps to replace his Bryston. I don't think that is the issue.

Kiplisch speakers typically have a very bright sound, and the NCore won't mask that like some other amps do, and that may be the issue you have now, you hear the bright Kiplisch sound.

 

[voodooless]

I'm talking about months of leaving it alone and using it casually, without thinking too much about equipment. You develop a general impression of the sound as a sum of experiences.

But that’s not how auditory memory works.

Sure, maybe that thing is that I'm deluded, and there's nothing sonic that can be perceived or understood as qualitatively different by a human being in audio reproduction at all, and the only thing that matters in the world is a bench measurement. I just don't particularly think that's true, or at all useful as a rigid, reflexive principle.

You’re not deluded, just as human as all of us. We’re really bad at this kind of thing. Auditory memory is extremely short, and we humans. Have no way of shutting off various stimuli that contribute to how we feel about what we hear.