dCS Network Bridge default bit depth in Roon

Hi my NB arrived recently and I find it’s recognized “Max bits per sample” in advance setting is 32.

From the dCS spec and the limitation of AES output, shall I change it back to 24?

I’ve tested both settings and feel the sound is slightly different. So want to know which is technically correct, to avoid any unfavourible data truncation. Or if NB can receive and process 32 bit data and there is advantage in generating the 24 bit AES signal this way.

Just leave it set at its default. Unless you’ve managed to find some 32 bit content there’s no difference either way.

thx and will setup accordingly.

Hi Andrew, is there any possibility that a future firmware update on NB will allow 384/24 PCM and DSD128 output from SPDIF (RCA)?

S/PDIF isn’t capable of supporting those rates.

But how come my Chord Qutest DAC’s SPDIF input can take 384/24 PCM and DSD128?

Also questions on the device setup for NB in Roon -
(1) for volume, the default setting is “Device Volume”, which I believe is the same as the digital volume control in NB’s own control app; the other option is “Fixed Volume”, which I initially thought would be more bit perfect or less alteration in the digital processing and let preamp to do the volume control at the analog stage. However, it for some reason sounded less dynamic than “Device Volume”. This is counter intuitive. Can you educate me on the reason? Does dCS believe that volume control at digital stage is better?

(2) for the “clock master priority”, what is this for? What does 1 to 10 mean and which setting value is the best for my setup (NB + Chord Qutest via SPDIF)? What value is assigned to “default”?

(3) some of these device settings are not even available in NB’s own app. Why through Roon we can do more to NB?


The specification of this DAC are not so clear on chord website and very strange from vendors. It seems it is using a dual data mode input (a bit like dCS ?) so why not higher resolution…but for toslink very difficult to understand how they can achieve 192khz as it should be limited to 96khz.
DSD64 in dop format on spdif or aes should be ok but dsd128…

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The S/PDIF interface is bandwidth limited to 24/192K. That means that the combination of driver /receive circuits, cable, and connectors can cause enough problems at higher rates that 24/192 is the fastest that the interface should be run in order to be assured of reliability. There’s nothing stopping someone from running the interface at a faster speed it just may not be reliable.

All that this option does is determine whether or not the volume control slider in Roon’s interface appears or not. When set to device volume the control in Roon’s UI operates the Bridge’s volume control. When set to fixed the control in Roon is not visible.

Something is either bit-perfect or it’s not. There are not varying degrees of bit accuracy.

This setup is for grouped playback in Roon. When playing to a single zone it has no function. This is a Roon setting, it has nothing to do with the Network Bridge.

These are all Roon settings and have to do with what Roon does to a stream BEFORE sending it to the Bridge. None of them are modifying the configuration of the bridge itself.

Thanks Andrew!

I have a similar experience. When set to “Device Volume”, sound is leaner, cleaner, longer decays, highs accentuated (definitely). I can separate instruments much easier during heavy orchestral passages. Maybe it has something to do with SPL. I felt “Fixed Volume” sounded louder. BTW, I do not employ NB (I wish someday very soon.). I use HQPlayer (over Ethernet). I find similar things on different connection strategies (i.e. direct connection to DAC USB port, via reclockers like Acousence isolator, which I believe employs XMOS).

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I thought less processing would yield better sound quality, but this setting is the opposite which is obviously beyond my understanding :sweat_smile:

Maybe this topic deserves a separate thread^^

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