I haven't seen any posts about this, and haven't received any feedback in the bug section, so I thought I'd start a thread and see if I have better luck. When sending DSD via coax DoP into the a-6 I am getting loud interruptions of intermittent noise a few times each track lasting a few seconds each time. The display reads DSD 64 the entire time, but the VU meters of course max out hard during the intermittent noise. The DoP is coming from a modded Oppo103 with a VanityHD board playing SACD passing DSD 64 in the DoP package unmodified through spdif. I'm trying to find out if this is an issue with the a-6 and if so, if there is a potential fix or if I need to return/sell and find a different streamer that can handle the DoP input. Thanks
You should be aware that there are some limitations to the max sample rate you can play on SPDIF coax, and that is 192 kHz, which I believe is far lower than a DSD64 in DoP... (I think that will give a 384 something kHz...), so, I believe there's no surprise in your results.
Vanity makes that module specifically to pass DSD64 in DoP via SPDIF coax, though, so I'd be surprised to hear SPDIF couldn't handle it. I believe the DoP package is read and transmitted through the coax as a PCM transmission within the sample rate limitation.
That would imply resampling (or, better, downsampling) but I cannot speak any more, as I do not know the module. Do you have experience being able to play such stream with another DAC through COAX, so that you can confirm the problem might be in the A6? Just asking, as I would do so.
Hey Nutul, I appreciate your input in this matter, thank you. Unfortunately, I have not been able to test it on another DAC because my current DAC, an older Lampizator L4G4, is a PCM only module. That's why being able to convert DSD to analogue directly was a big selling point for me of the A6. Your point is well taken, though, that the issue may lie not with the A6 but with the transport, which is why I'm looking for anyone to report that they've tried the DoP input as well. Regarding DoP, I thought the whole point of it to begin with was to fit DSD64 it (hide it) within a 192khz outer frame in order to allow it to convey it via SPDIF. In any case, I am going to run some other experiments when I get back to my apt tomorrow to see if I can determine if the problem might be coming from the Vanity/Oppo transport. In the meantime, I am just hoping that someone else has or will try DoP into the A6 and report whether it works fine or they experience the same problems. Thanks
I think more than a few have. Both native and DoP. Now that I look even better... DSD has its foundation on sampling frequencies that ARE MULTIPLES OF 44.1. This is per standard specification. Now, 192 is not a multiple of 44.1, it is of 48. I don't know the inner details of the DoP container, but 192 smells fishy already... it should be 176.4
yes, 176.4, I was just saying it fits within the parameters. But you are saying some have reported DoP input into the A6 via SPDIF without issue? If that is the case, then my problem likely does lie with the transport, or a defective A6. More likely the transport.
Better wording could be "I seem to remember"; mainly, there is a thread regarding the lack of a proper Windows driver to play native DSD, so the people are complaining they are "limited" to play DoP, which I understand as "they do play DoP, although might not be satisfied, as they would prefer native DSD". Actually, the above implies USB, not SPDIF... but searching should bring something about.
yes, I think I read through that thread, but if memory serves that was about trying to output DoP and DSD to a separate DAC. The issue i am having is with inputing DSD as DoP via SPDIPF from a transport into the A6's internal DAC for conversion. It works, the display shows DSD64 being converted to analogue, but is interrupted a few times per track by loud white noise. It's perplexing. Other than the intermittent noise, the conversion sounds really good, btw.
If the source was purely SW I'd scream for a buffer-size issue. Since it's a SACD through that "magic-box" (it surely has some software onboard)... does it offer some "tweaking"?
The firmware inside the Vanity module takes the raw DSD stream and packages it in standard 24bit PCM frames at 176.4kHz for sending over SPDIF. It is done with a FPGA, so yes, software effectively.
So... only alternatives: :-( - test the A6 with other source on coax - test the Vanity with another DAC and see if the same artifacts in terms of white-noise spikes are still there or not.
Yeah. I'm going to open the Oppo when I get back to my apt and change the output to PCM and see what happens at high resolution PCM via coax. Btw, normal rebook CDs work fine from the Oppo via coax to the A6 without any noise interruptions. In the meantime hopefully someone who has also tried DoP into the A6 via coax will chime in their experience.
