Which HQP Filter are you using? [2023]

DAC is Holo May KTE

7th order modulators are good for Holo DACs, such as ASDM7EC-super, ASDM7EC-light or ADSM7ECv3.

2 Likes

Thatā€™s what Iā€™m using on the modulator side. I was just wondering if there would be a certain filter to use with a vinyl rip. For my other listening Iā€™m using poly sinc gauss long and hires lp on nx

That is a good choice for vinyl rips too.

2 Likes

No, on Audio Core (macOS) you have max limit to DSD256. No more.

1 Like


Can do also poly-sinc-ext2 with same Modulator ASDM5EC-light on ifiNEO iDSD
DSD512x48

4 Likes

Anyone with an M1 Max Studio, can you confirm if it will do DSD512 (Sinc-MGa / ASDM7ECv3) or do you need an Ultra for that?

I donā€™t think any current Apple silicon Mac will do that.

2 Likes

Thanks for clarifying. I must have misread something the other day. Guess there is really no reason to give up my trusty MMM1

After getting HQP 5 going, I switched my Holo May SDM DSD256 modulator from ASDM5ECv2 to ASDM7EC-super. Comparable server load, but improved rendering of jazz piano especially, leaving behind a slight ā€œstickinessā€ between overtones, making each note on the piano (and double bass) more layered, less smeared. Not huge effects, but consistent and beneficial. Both with tube DNA Stellaris > ZMF VeritĆ© blackood and solid-state Ferrum Oor > ZMF Caldera kingwood.

7 Likes

Iā€™d recommend trying v3. You might like it even more than super. :smiley:

1 Like

I tried ASDM7ECv3 and ASDM7EC-super and definitely prefer super!

3 Likes

Agree!

ASDM7EC-super
1x poly-sinc-gauss-xla
Nx Sinc-Ls
DSD 512 x48
Holo Spring 3 KTE

2 Likes

You should also try ASDM7EC-v3 before committing to ASDM7EC-super. There seems to be a real split in preference between the two, all else being equal. I personally prefer -v3 over -super.

5 Likes

Iā€™ll be on vacation next week and Iā€™ll have plenty of time for a -v3 vs -super bakeoff, thanks all for the suggestions :grinning:

1 Like

Iā€™ve just installed a new DAC (Mola Mola Tambaqui), which I can use over the LAN (Roon Ready) or via USB if i want to pre-process with HQP. Given that the DAC upsamples incoming PCM to 32-bit/2.8MHz, Iā€™m not sure if HQP will actually provide any significant advantage (the DAC sounds jaw-droppingly good anyway, but very happy to try the experiment. Any suggestions then as to a starting point for HQP filters?

3 Likes

You have a lovely DAC. I was using a Chord DAC which also upsampled and I had issues with feeding HQP signals, so I decided to go NOS which is the best decision I ever made regarding DAC and signal feed with HQPā€‹:musical_note::musical_note::musical_note:

2 Likes

Your DAC is restricting HQPlayer capabilities, since it doesnā€™t have bit-perfect conversion. But you can still benefit from HQPlayerā€™s filters, by feeding the DAC at maximum possible PCM rate it can accept over USB.

1 Like

For clarity, it accepts DSD (native or DoP) up to DSD256. Iā€™m not entirely clear what its processing chain is for DSD after that, but if itā€™s remapping to 32-bit3.125MHz (not 2.8) vs 1-bit11.2896, where does the ā€˜not bit perfectā€™ part come in?

There is PCM rate down-conversion for DSD inputs, which then get oversampled and run through the 1-bit modulator again for the conversion stage. Thereā€™s no direct pass through of DSD data straight to the 1-bit D/A conversion stage.

DSD getā€™s converted to 176.4 or 352.8k PCM:

5 Likes