I am running the DCS Bartók with Roon and I noticed my 32 bit files get converted back to 24 bits over PCM. If I run those same files from e.g. JRiver the Bartók has no problem accepting the 32 bit files. Is there a way I can get this to work in Roon too? I can only select 16/24 bits from the dropdown box.
Thanks for your thoughts and advice
Hmmm. That’s surprising. I have an MSB DAC, also Roon Ready, and it accepts 32 bit input.
If you look under Settings>Audio>DCS Bartok>Device Setup>Advanced Settings you should see Max bits per sample (PCM) set to 32. If it is set to something less, set it to 32.
If that is set to 32, can you show your signal path? There may be some DSP in-line that is affecting this.
What is a 32-bit file? I thought they only went up to 24 bit?
Andrew should be able to help you. @AMP
Hereby my settings
and the drop down box opened
And the signal path for the track
With my RME interface, RME engineers provide test files to test bit perfect playback. 16, 24 and 32 bit test files are provided by RME.
If the entire chain is bit perfect, then the interface will display the message on it’s screen.
16 bit and 24 bit test files pass, with Roon. 32 bit test files fail this bit perfect test with Roon…
Audirvana is the same.
Hilariously the only program I have that passes the 32 bit test file is the only program really never intended for bit perfect playback - HQPlayer. It’s designed for DSP. There’s a painful way to turn off all the DSP processes in HQPlayer and that works. RME themselves also acknowledge that HQPlayer is one of the few programs capable of 32bit bit perfect playback.
Andrew from DCS should be able to get to the bottom of this.
My MSB takes 32-bit fine. But true, in this audio chain there is DSP going on.
James from dCS here. This is expected behaviour - the Bartók will only work with a maximum of 24-bit signals. We don’t let the unit report that it is able to accept signals which it cannot actually process internally, such as accepting a 32-bit signal which would then need to be decimated to 24-bit anyway to be of any use to a DAC.
As an aside, digital to analogue converters, including the Bartók, currently are only capable of running at a maximum of 24-bit. The voltages involved in 32-bit conversion would be so small that they are well below the tolerance of any known analogue components. To give an example, for a ladder DAC to be capable of even genuine 24-bit resolution, the current source for the most significant bit needs to be accurate to 0.000006%.
Thank clear. Also checked JRiver, it does indeed convert the 32Bit files back to 24Bits
Thx James! Very clear point.
And a genuine 32-bit resolution ladder would require a current source accurate to 0.000000023%. And just for laughs, 16-bit would require a noise level below 0.0015%. Crazy numbers.
And since I am on a roll right now… here are the voltage precisions required for a 2V most-significant-bit max output:
16-bit 30 microVolt
24-bit 0.1 microVolt
32-bit 0.0004 microVolt
which is insane…