DAC + Volumio I2S arbitration ?

Out of curiosity I’ve just made a cable (see pic) to run from the Audiophonics DAC’s I2s port to a Teralink USB converter. On the Teralink there is a direct I2s output.

Probably a stupid question but is it possible to have the DAC connected to the Raspi AND at the same time to the Teralink ? Can the Raspi or Volumio arbitrate between the two ?




I am assuming your question relates to one DAC and not 2 off units.

I could ask why but if we didn’t try stuff we wouldn’t learn anything :laughing:

I would say yes, by enabling and disabling the I2S driver. Whether it could be done without a reboot, maybe someone else can advise.

Coming from an electrical background I would also prefer to isolate the I2S cores with a switch, but that’s electricians for you :wink:


That is what I thought. Basically, as things stand it is either / or.

The idea was to have an extra USB in port from my computer to the DAC. But maybe that would be achievable directly to the Raspbi USB port ? Is that possible? :wink:


Reckon not, in any case that would be just like mounting the music from pc hdd to rpi :astonished:

Ethernet would be a different approach. Use pc as a media “server” and the rpi + dac as the music “renderer/sink” :bulb:

My approach would be to go with the sound i prefer, rpi + dac or pc + teralink + dac.

So what sound do you prefer ?
I would be interested in how you think the teralink and pc compares to the rpi option, particularly from a sound quality and reliability point of view :question:


Subjectively, I think the pi + I2S DAC is the simplest and most dynamic configuration in my office system.

Hard to compare it to the Teralink since it normally feeds into a Beresford Bushmaster DAC which is a very nice sounding DAC imho. But there are more conversions going on there so maybe yes it does sound a little flatter.

My office hifi is not the best resolving system (SMSL SA50 with Teufel Speakers and a mish mash of assorted cables). But definitely, the pi + I2s sabre DAC used over Shairplay is a very good sounding configuration and it replaces a DAC, Teralink converter and a Airport Express. It is very robust. It has been running for days on end without the slightest hiccup.

If I put the pi+I2S DAC into a more resolving system with dedicated cables it comes very close to a Yulong DA8 DAC fed via USB. My brain is trying very hard to fault the pi + Sabre DAC because it is about a 1/10th of the price of the Yulong DA8 :astonished: :stuck_out_tongue: … But I think the Yulong does have an edge in refinement and dynamics (expected) but is very close.

In another Volumio setup, I had the Yulong fed via a cubox-i2 (Shairplay - USB - Yulong) which worked great and replaced an Airport Express and gave me the possibility to use the USB port of the DAC (Airport Express only has a optical out) and higher sampling rate of 48kHz vs 41kHz. Funnily, when I use the raspi in place of the cubox I only get 41kHz.


I think we have found similar results, the RPi + i2s DAC provides great quality / £ spent. I have tested the Audiophonics ESS9023, Wolfson Audio Card & IQaudIO Pi-DAC and all provide a similar quality of sound. This also compares favourably to some USB DAC’s that I have tested in the £ 100 - 500 price range.

The 44.1 kHz vs 48 kHz may have something to do with shairplay(apple) vs upmpdcli(DLNA/UPnP).

My experience with Airplay & Shairport is that in streaming they unsample 44.1kHz to 48kHz. They will also downsample source data > 48kHz to 48kHz.

Whereas the upmpdcli(DLNA/UPnP) will maintain source sampling rate at 44.1Khz.