HQ Player

[asdf1000]

11 hours ago, Luca72c said:

Jriver (and others) has virtual audio device functionality on windows and mac, so it is feasible.

 

Not on macOS... https://yabb.jriver.com/interact/index.php?topic=125054.0

 

 

[asdf1000]

Hi @Miska

 

I know with Bluesound Node2i (TOSlink) feeding USBStreamer feeding HQP OS, you said input TOSlink jitter is not an issue. HQP OS has a clever way of dealing with this TOSlink jitter.

 

But is it the same on HQP Desktop, with same TOSlink source and USBStreamer connected to macOS?

 

Is jitter from a jittery TOSlink source managed the same on HQP Desktop and HQP OS?

 

Or does macOS get in the way of how you can manage incoming jitter, compared to HQP OS?

 

[asdf1000]

17 hours ago, Miska said:

 

It is handled same way always, not depending on the OS or HQPlayer product.

 

 

I guess the miniDSP USBStreamer itself plays the biggest part in removing jitter, since it is the part converting from jittery TOSlink to USB and providing clock to mac/PC ?

 

[asdf1000]

Hi @Miska

 

When reading the Ayre Whitepaper below, which HQP filter comes closest to their idea of ideal transient response?

 

poly-sinc-mqa-mp ?

 

It appears poly-sinc-short-mp has longer post-ringing than poly-sinc-mqa-mp and Ayre's idea of ideal is min phase + fewer post ringing cycles.

 

Granted, there's no info about roll-off frequency and stop-band attenuation but if it's only 1 cycle post-ringing...

 

https://www.ayre.com/wp-content/uploads/2020/08/Ayre_MP_White_Paper.pdf

 

[asdf1000]

23 hours ago, Miska said:

 

Maybe yes, or minringFIR-mp. Although none of the minimum-phase are as short as Ayre's. polynomial-2 is even shorter, but linear phase.

 

 

Well, from the response plot you can see that it leaks almost throughout to 44.1k.

 

This a bit older measurement set, so it doesn't include the filter measurement as such, but you get idea from the IMD test.

 

https://www.stereophile.com/content/ayre-acoustics-qb-9-usb-dac-measurements

 

 

For impusle response of HQP filters, which filter has the highest 'signal to noise' ratio?

 

With the noise in this case being the pre and post ringing and the signal being the impulse itself.

 

Is that relevant in any way? i.e. the amplitude of the impulse response relative to amplitude of the ringing?

 

When I look at the filters Archimago plotted, if I eye-ball it, sinc-M? Maybe closed-form?

 

 

 

 

[asdf1000]

21 hours ago, Miska said:

Not sure what you are asking...

 

Ringing is part of the impulse response.

 

Thanks Jussi. I try to ask again with pictures, see attached. But I think I get what you mean from you reply.

 

I know ringing is part of real world IR but ideal transient response should have zero ringing? Analogue signal?

 

So the ringing is "noise" is a sense? And the sample is the "signal" ?

 

So in the attached, the fact that "x" is larger than "y", does that have any relevance or significance to anything?

 

Is the IR with "x" closer to the analogue waveform because it is the highest "signal to noise" ratio?

 

I don't think SNR is a term you DSP gurus apply to impulse responses but hopefully you get what i mean - the ratio between sample peak and the highest ringing peak.

 

 

 

 

 

 

[asdf1000]

2 minutes ago, Miska said:

 

That would be analogue signal with unlimited bandwidth. With digital, you are always limited to bandwidth of fs / 2. Which is the reason for all the filter stuff in first place. If you want to get closer to ideal transient response, you need to stick to DSD domain.

 

 

No... :D

 

 

Not really. The sum of the impulse response is filter gain, which is most cases is 1.

 

 

This is kind of dangerous waters... Because you should really also look into frequency domain version of the impulse response in parallel.

 

 

LOL thanks.

 

So in summary - the fact that x is larger than y in the images I showed doesn't actually mean anything, when talking about transient response ?

 

[asdf1000]

14 hours ago, Miska said:

Are you listening to progressive rock recorded in small separate studio cabinets and mixed into one piece on a mixing desk.

 

Modern electronic, pop, urban music etc would all fit in this same category right?

 

poly-sinc-short-mp would be ideal for these styles?

 

These genres are mostly mixed entirely on computer these days (they call it "in the box")