My apologies for distracting with my earlier reply, Ozzy. I am NOT running that new board, but rather the original.
jedi 1,
Yeah I think the original Juli board did not have the issue. The Bryston newer IAD board was designed to improve sound quality with the XLR/RCA digital outs.
I sure hope Ted keeps this on his radar and can help.
ozzy
Ted, Paul,
Its been over a week now any updates/plans or progress?
ozzy
Iām not working on it until I finish my current task. Iām sorry if I gave the impression that it would be a quick fix. When I start it may take a day or a week or so.
Ted,
Ok, I thought you said in a week you would be working on it. But ok, please keep it on your plate.
Thanks,
ozzy
hey folks. just seeing this thread nowā¦
Iāve been using a BDP1 for about 5 years and love it. so much. that I recently purchased a BDP2. itās in transit as I write this note, due to arrive in about a week.
one of the benefits of the BDP2 vs. the BDP1 is the USB outputā¦and I plan to use the usb output for DSD files.
I am using a Direct Stream DAC (also love it!).
the BDP2 I purchased has a manufacture date of 2016, and has the upgraded board installed.
I hope it runs distortion free 
Iāll keep yāall posted.
cheers!
tj-sully,
It will on HR files greater than 24-96hz.
ozzy
tj-sully,
Have you received the Bryston BDP-2 yet?
ozzy
hey Ozzy, it arrives tomorrowā¦
Iāll post an update once itās all set up and Iāve had a chance to listenā¦likely this weekend. stay tuned!
cheers, TJ.
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hey Ozzy
Listening to my BDP2 today. Tried playing some 192 PCM files. you are absolutely right. The Direct Steam will only play 192 files using the USB output from BDP2. The AES/EBU and coax are duds.
My 192 library isnāt very extensive so not a significant issue for me. But I can see how this would be troubling if using 192 files on a regular basis. sorry man.
TJ
tj-sully,
Thanks for your update. Yeah I do have many 24/192 hz files that will not play.
Ted, Paul, I hope you and everyone on this forum has a Merry Christmas and I hope you can resolve this problem soon.
ozzy
I had a BDP-2 with the old sound card and was reluctant to upgrade to the BDP-3 for the reasons stated in this thread. However, when I read the threads closer I noticed that the problem only surfaces with 24/192 hz files of which I have none. So I went ahead and upgraded recently and have had zero issues. If I do ever happen to own a 24/192 file I figure Iāll just use the USB output, which to my ears sounds every bit as good as the AES/EBU connection I typically use.
Thanks moredins, and Merry Christmas!
Unfortunately, I do have many 24/192hz files and for other reasons I would rather not play them through the usb.
Also, I paid good money for the new Bryston upgraded IAD board and I would like to be able to use it.
ozzy
Merry Xmas Ozzymilton. I totally understand where youāre coming from on this and hope it gets taken care of and fixed. I appreciate the fact that youāve stuck with trying to get this problem addressed for so long.
Thanks again. I tried to address this problem before and it looks like PS swept it under the rug.
Now, I would like it finally addressed by PS audio. It is now a well known documented problem.
BTW, my name on Audiogon is ozzy and many others are interested in a fix.
ozzy
Not a Bryston owner, just technically very curious about why this problem could exist. @ozzymilton can you ask your āmany othersā if any of them are in a position to get an oscilloscope trace from the coax output when playing at 192kHz? Itād be especially interesting to see the voltage of the SPDIF peaks.
In one technical respect, 192kHz SPDIF is the most challenging encoding for the DS DAC to receive: the signal has a switching frequency of over 24MHz. Thatās more than twice as fast as native DSD256 on I2S. So with 192kHz SPDIF the FPGA needs to observe a level change (or the absence of one) every 6 to 7 of its own clock cycles, compared to every 15 cycles for DSD256.
The FPGA isnāt reading the SPDIF input directly, itās seeing the output of a comparator circuit thatās reacting to the input signal. The comparator gets āpulledā one way and the other depending on what the polarity of the input signal is. But that mechanism has capacitors in it which need to charge to a certain level before the comparator flips it output from one state to the other. How quickly that happens depends partly on the actual voltage differential of the incoming signal, and if the Brystonās SPDIF output signal is unusually low in voltage terms, then when the signalling is happening at ~24MHz there may not be enough time between transitions to charge those capacitors and flip the comparator for the FPGA to see it.
This could explain why the Bryston works with the DS DAC at lower frequencies, where thereās more time between transitions to charge those capacitors and flip the comparator. And the Bryston would work with just about every other DAC in the world because they all use off-the-shelf SPDIF receiver chips rather than Tedās custom circuit.
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dvorak,
The problem exists because the PS Dac is off the standard spec.
A lot of words does not equal a solution.
And BTW, if you had this incompatibility problem wouldnāt you want it corrected ?
ozzy
If youāre as uninterested in the engineering as you appear to be, then thereās not much value in talking about standards and specifications.
The request (initially from Ted IIRC) to see some scope shots of the Brystonās output relates directly to the question of standards compliance: if the output signal falls within the range of 0.2V to 0.6V peak-to-peak then itās within spec and the āblameā, so to speak, might fall on the DS DACās side. But I offered a reasoned hypothesis about why an unusually low signal level might cause the DS DAC to be unable to track the high speed transitions ā and if the Bryston gives less than 0.2V then we might say their product is the one that doesnāt meet formal expectations.
Of course it could be something else entirely. Nobody will know until some actual investigation is done, and that canāt go beyond hypotheses until thereās some actual data to look at.
A complaint requires only a small number of words but achieves nothing by itself. Because you have this incompatibility problem arenāt you the tiniest bit pleased that somebody is interested enough to invest this many words and the time behind them to try and understand what the nature of that problem might actually be?
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Ozzy
If as you said the BDP-2 worked correctly connected to the DS by coax with the original board and only started having problems when you added the upgraded board Iām not sure why finding and correcting a problem caused by Bryston hardware is Ted or Paulās problem to solve. As you have stated multiple times this problem only occurs with certain BDP-2 outputs yet you refuse to use ones that work and are available on both units. It seems to me that Mr. Tanner and his tech people need to resolve the issue as you are their customer too and their āboard upgradeā caused the issue in the first place. They just donāt have a public forum to complain on and it appears their little forum is dead in the water and yet no posts on it about your problem by you.
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I have an Innuos Zenith MK3 connected to my DSD Sr. DAC via the USB and I can play 24/192 hz.
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