Which HQP Filter are you using?



How are you monitoring the GPU load?

(Andrew Cox) #27


Works pretty well for the price (free) except the controls are non-responsive over RD on my iPad if it auto starts. Closing it with Task Manager and restarting it the controls are ok.


Sorry for the stupid question but are the new mqa filters in HQPlayer related to Meridians MQA Format, and if yes, what’s the relevance?

(Jeff) #29

Jussi is no fan of MQA. I believe he created the filters to bandaid some of the problems with unprocessed MQA files.

(Jussi Laako (Signalyst)) #30

Yes, those filters are multi-use. When used for undecoded MQA files, it removes some of the unwanted noise added by the MQA coding. When used for decoded MQA streams in HQPlayer Embedded (coming from Tidal application, Audirvana, etc) it works as “MQA style but better” slow-roll-off very short upsampling filter. And in other cases it is suitable for use with hires content if such short slow-roll-off filters are desired.

When MQA encoded files are played directly by HQPlayer, there’s also additional MQA noise removal process employed.


Attempting to bring an old thread back to life :grin:

I’ve mostly been enjoying poly-sinc-short-lp-2s (DSD512) with my planar magnetic MrSpeakers Aeon Closed cans, for a few months now but these last few weeks Ive been enjoying poly-sinc-ext2 (DSD512).

From the manual, poly-sinc-ext2:

Linear phase polyphase sinc filter with sharp cut-off and high stop-band attenuation for extended frequency response while completely cutting off by Nyquist frequency (non-halfband). Processing is two stages with minimum factor of 16 before applying special second stage. If difference between source and output rates is less than 32x, operates as a single stage with only the first stage.

Anyone else given poly-sinc-ext2 an extended audition?


Hi Sean, i’m using poly-sinc-ext2 (ASDM7 / DSD256) daily and like it.
Good SQ to my taste (deep, good bass and still “precise”) , not too “heavy” on CPU.

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(Andrew Cox) #33

I’ve been using poly-sinc ext2 for a few weeks now with DSD7 256+ fs. Upsampling to DSD 512. I’m liking it a lot. Extended highs and good transients with linear phase. What’s not to like ?

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Good transients with linear phase - so you’re in the Rob Watts camp, not the @jussi_laako camp ? :stuck_out_tongue_closed_eyes:

Although you did say good transients - not best or better… hehe

Just poking fun of course. Don’t mean to re-ignite a religious war :grin:

I’m loving ext2 a lot also.

(Andrew Cox) #35

I probably upset both of them because I usually feel linear phase is a bit shy with transients. But ext2 has good natural sounding transients to my ear.

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(John B) #36

And now for something completely different…

I’ve actually gone no upsampling going straight ahead PCM to HoloDAC and it has a certain charm…


(Jeff) #37

Sounds like ext2 is a winner, I did like ext when I had my Devialet!

(Andrew Cox) #38

Well it is always worth checking the emperor actually has clothes on. I haven’t tried Qobuz hi-res PCM with NOS. Something to do this week.

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(Dirk De Taey) #39

For me it is not. I still prefer poly-sinc-xtr-lp (non -2s)

But I know EXT2 is preferred by many, even by Jussi himself these days.

(Jussi Laako (Signalyst)) #40

I’m not using the PCM mode of either Spring 1 or Spring 2. I always stick to DSD. And my Cyan is DSD model anyway…

At the moment I’m using Spring 2 and Cyan at DSD256 with poly-sinc-ext2 and ASDM7. Spring 1 is running at DSD512 but otherwise same settings.

For best PCM mode performance on Spring 1 or 2, set “DAC Bits” to 20 and use either noise shaping or TPDF dither. Spring 1 running at 352.8/384k and Spring 2 at 705.6/768k or 1.4112/1.536M. On macOS to reach the 32x rates you need to set “DAC Bits” to 16 to make it work and then use either NS5 or NS9 to reach equivalent audio band SNR as with the 20-bit mode.

In these cases, of course DAC is set to NOS mode so that it doesn’t mess with the inputs.


Added bonus is because it’s always running in -2s, there’s no need for an uber computer for 2-channel.

Multi-channel at DSD256 may need serious horsepower (CPU + GPU).

My fanless cased NUC7i7DNHE does 2-channel PCM44.1 to DSD512.


My new favourite for up-sampling to PCM705/768kHz is sinc-M…

(Spencer Marquart) #43

This has been my go-to setting for a few years now. PCM, no DSD. Sounds really great. LOVE HQPlayer!

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Yes, I am currently using poly-sinc-xtr-lp upsampling all PCM to 352.8 with my DirectStream DAC. It’s the filter I like the best. Although I have to say the difference between it an poly-sinc-ext2 is small and on any given day I might not be able to to notice the difference.

(Jussi Laako (Signalyst)) #45

ext2 and xtr are very similar, especially for PCM output. Main difference being shape of the roll-off curve. For SDM output the ext2 being also different by the different intermediate rate compared to xtr-2s.