Even if he is mistaken, one thing is that I’ve never read anything like this from Rob.
There is a place for both HQPlayer and M-Scaler, there is no reason to get resentful or nasty.
It would be much more fun if two of you had a friendly conversation on your approaches.
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When I read this kind of response it usually means you don’t have the ability to contradict what was written.
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So via NAAD, HQP ‘knows’ what the DAC’s maximum input rate is and upsamples to that ‘automagically’? ANd hence all the DAC’s internal filtering etc is bypassed?
HQP upsampling level is configured by you. Once configured, HQP always upsamples to the configured level.
Question.
If I used a HQPlayer to upsample via Roon and pass that to my ultraRendu endpoint with USB out, can I take that 705/768 kHz Signal via a USB to my Chord Qutest? Or does the Qutest only take that sampling rate in via its dual BNCs?
It can, but the PCM768 would sometimes cause the stream to break and transform to white noise on one of the channels. PCM705 works ok though. After extensive testing, I came to the conclusion that this is because some kind of incompatibility between Linux OS and the USB interace used by this DAC.
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IS not necessarily the best resolution at which that DAC operates.
Doh !
is that ‘knowable’ other than through the wonderfully subjective method of listening?
for me it’s about bypassing any internal filtering on the DAC itself once HQP has done its thing and @andybob implies that when you max out the DACs input rate
logically i suppose a NOS DAC is in order here, no?
not sure any of those do DSD though
I use the Holo Audio Spring. I have a I but the II is the current model and has an improved USB input and a 48k family oscillator as well as 44.1k.
The Spring has 4 boards of resistor ladders. Two each for PCM and DSD, the second board being used to correct linearity. So DSD is handled natively without any conversion to PCM.
I exclusively use the NOS setting on the Spring, meaning the HQPlayer server does all the DSP work and the DAC does as little as possible to turn it into analog.
I’m not entirely sure, LOL. I’ve just seen posts by @jussi_laako where he has mentioned that the “best” resolution for a DAC is not necessarily the highest available resolution. Or, I could have just had a brain freeze and misunderstood/misremembered those posts.
“Usually” means you have no idea about my experience with embedded, handheld or supercomputering or image and signal processing software development…
The Chord Qutest USB input supports 768kHz PCM and DSD up to 256 via DoP (Mac) and native DSD up to DSD 512 playback via ASIO driver for Windows…
An outstanding question is where in the input processing path does the duel BNC inject the data in the signal processing chain verses the USB input… Rob suggests “when an M scaler is connected, the WTA1 filter is not used, and it is passed through to the 256 FS WTA 2 filter.”
WTA1 should be bypassed the same way when you input 705.6/768k through USB.
DSD inputs are converted down to this same rate PCM.
It applies to some discrete NOS DACs that can actually run the conversion section at different rates may be subject to this. Such as Holo Audio and Denafrips.
But another aspect is that EC modulators make enough difference that given current computing performance limitations you may still prefer using DSD256 output rate instead of higher ones and non-EC modulators.
Thanks, for clarifying.
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You should be able to do this while using USB input but depending on your endpoint you may run into issues especially when switching from 705khz to 768kHz and more often when playing at 768kHz as @Sebastian_Tomita mentioned. However it seems to depend (in my experience) on the endpoint, both hardware and OS. I had the problem with microRendu (with Chord TT).When my endpoint was a Pentium NUC with 4GB of Apacer RAM, running Euphony OS + NAA, I had the problem (With Chord DAVE) . When I ran Audio Linux on the same Pentium endpoint and NAA, the problem went away. When I connect my i7 NUC server directly to Chord DAVE I do not have the problem either.
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What would be your reccomended settings for the Denafrips Ares II? Should I leave the DAC bits as default or should I set a smaller number? Would DSD be a better option than PCM. If so, what resolution and what modulator? Thank you!
I use an Aqua La Scala Mk2 Optologic DAC which is an r2r like yours. Jussi actually recommended to use “20” as the bit rate And not 24. I’m assuming that this should be used for you also.
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The sense of achievement in setting up a Roon system, with a ROCK, then linking HQplayer getting the numbers squeezed out gloriously by my Qutest has been pretty much destroyed by reading this thread.
So back to the OP; does anyone have suggestions?
…and I really don’t care if you don’t think I should
With Chord dac I would suggest pcm, sinc-M, 768k, lns15, adaptive rate checked. That is my setting with TT2.
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