Hypex Ncore vs D chip amps - sound quality?

[elshaddai]

If you take the different power output options (through internal or external PSUs) off the table, do the current Class D chip amps measure up to a Hypex Ncore? Will a TPA3255+PFFB sound the same top-to-bottom as a NC252MP at 2 watts with a 4-ohm speaker? Or is there still something unique/different about Hypex/Purify/etc. that puts them a level up? And/or do they all sound the same now and it's just power handling that differentiates need?

 

[DVDdoug]

Generally, if the amp isn't over-driven into clipping I don't expect to hear any difference between amplifiers unless there is audible noise. And that also depends on the sensitivity of your speakers, how close you are to the speakers and any other ambient noise in the room.

There's more to amplifier design that the chip so you'd have to measure a particular amplifier.

 

[Old_School_Brad]

The implementations vary. Which amplifiers in particular?

 

[elshaddai]

The implementations vary. Which amplifiers in particular?

None specifically in mind. I have an NC252MP, but it's overkill for my desktop - was just wondering if the new chip amp implementations would provide equivalent sound quality for much less money. Replace the Hypex with a mini amp and add a miniDSP or better speakers, for example.

 

[tomtoo]

Could there be a difference? Maybe. But from my point of view there is no reason why a difference should be there. The problem is that any imagend difference will propably much bigger than the real one where we come to the point that hurts. To realy know you had to do a blind abx. What is a pain in the axx.

 

[terryforsythe]

If you take the different power output options (through internal or external PSUs) off the table, do the current Class D chip amps measure up to a Hypex Ncore? Will a TPA3255+PFFB sound the same top-to-bottom as a NC252MP at 2 watts with a 4-ohm speaker? Or is there still something unique/different about Hypex/Purify/etc. that puts them a level up? And/or do they all sound the same now and it's just power handling that differentiates need?

The very inexpensive class D amps, at least the ones where I have seen the test results, tend to have a frequency response that is load dependent, especially with reactive loads. It may or may not be audible, E.g.:

Fosi Audio ZA3 Balanced Stereo Amplifier Review

Fosi Audio ZA3 Balanced Stereo Amplifier Review

www.erinsaudiocorner.com

If you have DSP (e.g., a WiiM streamer, a miniDSP or computer software) and a microphone, you should be able to add parametric equalization to compensate.

 

[elshaddai]

The very inexpensive class D amps, at least the ones where I have seen the test results, tend to have a frequency response that is load dependent, especially with reactive loads. It may or may not be audible, E.g.:

Fosi Audio ZA3 Balanced Stereo Amplifier Review

Fosi Audio ZA3 Balanced Stereo Amplifier Review

www.erinsaudiocorner.com

If you have DSP (e.g., a WiiM streamer, a miniDSP or computer software) and a microphone, you should be able to add parametric equalization to compensate.

Thanks for calling that out - I'm assuming the new PFFB "feature" is addressing that particular shortcoming, but it's not universal yet. Hopefully the next generation of chip amps will include that by default.

 

[kyuu]

Keep in mind that the load dependency will only result in an issue if your particular speakers have a high impedance at high frequencies (and maybe not even then). For example, let's take a look at that Fosi's chart and the impedance curve of my speakers:

As we can see, the load dependency on that Fosi ZA3 only really starts to become a significant (for various values of significant, considering the worst case is less than 1dB of rise) issue past 7kHz or so. Coincidentally, the speaker is down at 6 ohms at 7kHz and impedance is less than that for all frequencies higher than that, ending at roughly 5 ohms at 20kHz. By my estimation (someone do correct me if I'm wrong), if I were using the Fosi ZA3 to drive my speakers, the load dependency would cause at most a very negligible rise in the frequency response at the highest frequencies and would likely not be audible.

 

[elshaddai]

Keep in mind that the load dependency will only result in an issue if your particular speakers have a high impedance at high frequencies (and maybe not even then). For example, let's take a look at that Fosi's chart and the impedance curve of my speakers:

View attachment 392109

As we can see, the load dependency on that Fosi ZA3 only really starts to become a significant (for various values of significant, considering the worst case is less than 1dB of rise) issue past 7kHz or so. Coincidentally, the speaker is down at 6 ohms at 7kHz and impedance is less than that for all frequencies higher than that, ending at roughly 5 ohms at 20kHz. By my estimation (someone do correct me if I'm wrong), if I were using the Fosi ZA3 to drive my speakers, the load dependency would cause at most a very negligible rise in the frequency response at the highest frequencies and would likely not be audible.

Thank you - I'm using a pair of Philharmonic bookshelf speakers with a listed nominal impedance of 4 Ohms (3 Ohms minimum, 11 Ohms Maximum), but I don't have a graph for them. I'm guessing 11 Ohms wouldn't qualify as high impedance.

 

[kyuu]

Thank you - I'm using a pair of Philharmonic bookshelf speakers with a listed nominal impedance of 4 Ohms (3 Ohms minimum, 11 Ohms Maximum), but I don't have a graph for them. I'm guessing 11 Ohms wouldn't qualify as high impedance.

Which Philharmonics?

 

[elshaddai]

Which Philharmonics?

Just the True Minis - desktop setup. Currently have a JDS Labs Atom 2 DAC/HPA as a preamp and the NC252MP from Buckeye. Perfectly happy with those components - just curious if downsizing with no loss in sound quality would allow me to sell this set up and save some cash for a speaker upgrade.

 

[Guddu]

If you take the different power output options (through internal or external PSUs) off the table, do the current Class D chip amps measure up to a Hypex Ncore? Will a TPA3255+PFFB sound the same top-to-bottom as a NC252MP at 2 watts with a 4-ohm speaker? Or is there still something unique/different about Hypex/Purify/etc. that puts them a level up? And/or do they all sound the same now and it's just power handling that differentiates need?

I think it’s worth considering for you to try TPA3255 PFFB amplifier, Amazon has easy returns and there nothing better than trying yourself.
Or probably exchange with someone for a week or two to try.

 

[Guddu]

I think it’s worth considering for you to try TPA3255 PFFB amplifier, Amazon has easy returns and there nothing better than trying yourself.
Or probably exchange with someone for a week or two to try.

And just to add, your hypex may not have any considerable higher power as compared to tpa3255 with 48v 5a psu…. Just couple of bB perhaps.

 

[elshaddai]

And just to add, your hypex may not have any considerable higher power as compared to tpa3255 with 48v 5a psu…. Just couple of bB perhaps.

Understood -- I rarely push the Hypex, typically 60-80 dB unless I'm home alone. lol

 

[Old_School_Brad]

Keep in mind that the load dependency will only result in an issue if your particular speakers have a high impedance at high frequencies (and maybe not even then). For example, let's take a look at that Fosi's chart and the impedance curve of my speakers:

View attachment 392109

As we can see, the load dependency on that Fosi ZA3 only really starts to become a significant (for various values of significant, considering the worst case is less than 1dB of rise) issue past 7kHz or so. Coincidentally, the speaker is down at 6 ohms at 7kHz and impedance is less than that for all frequencies higher than that, ending at roughly 5 ohms at 20kHz. By my estimation (someone do correct me if I'm wrong), if I were using the Fosi ZA3 to drive my speakers, the load dependency would cause at most a very negligible rise in the frequency response at the highest frequencies and would likely not be audible.

This might be of interest in this context:

Complex impedance load amp FR influence - WiiM Amp review by Erin

It is quite clear these kinds of deviations are generally audible in A-B tests. Cheers. Do you have a link for that?

www.audiosciencereview.com

It seems not true to relying on that only high impedance cause the chip amps to deviate from flat response. E.G. Wiim amp and Klipsch Forte IV:

Complex impedance load amp FR influence - WiiM Amp review by Erin

That's what I call Audio Science :)

www.audiosciencereview.com