Are two DACs being used in my current setup?

Hi all.

Currently I’m running Core from a fully updated Windows 10 machine that has an Creative Audigy sound card that is TOSLINK’ed to my YAMAHA RX V675 AV receiver then to Cambridge Audio Minx speakers, and Headphone Out from the same soundcard to my cans.

Both DACs (receiver and soundcard) support 192khz/24bit signals.

All music files are coming from an external USB attached to the windows machine.

I’m not completely happy with this setup but have been given a NUC that I will be using with ROCK soon.

In the meantime I’m curious as to what is actually happening with my signal to the receiver in this current setup.

The Core is pushing the signal into (or through) the soundcard DAC, goes through the TOSLINK and into the receiver that also has a DAC? (I’ve read that TOSLINK only supports 96khz. I could be mistaken, and I’m not playing anything over 96khz anyway, so I think that point is moot.)

What DAC is being used in this instance? Are they both in play? Are there potential issues doing this. Is one of the DACs just passing through the signal to the other one?

I’m learning a lot reading these forums, so I thought someone here would be able to let me know what’s up here.


I use a Mc C2700 into Linn SelectDSM with Katalyst DAC. Both the 2700 internal DAC and Linn DAC together work fine.

Thanks for the reply.

I’m presuming that the Roon Signal Path is displaying the signal from Core to the soundcard, as I’m getting lossless purple stars.

I do wonder if the soundcard could only support 44.1 or 48 what my signal path would show, if both DACs are in use then would I be getting the full potential of the receiver DAC if it’s going through a sub-par soundcard first?

It’s more a curiosity for me, and the more I know about all the elements in my setup the better informed I’ll be.

It’s not really an issue for me atm other than the soundcard having 5 different outputs to choose from in Roon that is messing with my head, but thats another story.

This will all be redundant soon when I can take the core away from Windows and just use the soundcard to output to my cans. But then I’ll be looking at headphones amps, pre amps blah blah blah… Not sure my bank account is enjoying the hobby as much as I am.

you are only using the Yamaha receiver’s DAC. TOSLINK only transports digital data, so the DAC in your computer is being bypassed. Two Digital to Analog converters cannot be used one after the other. The first DAC converts a digital signal to an analog one, which the second DAC can’t do anything with since it is already converted to analog


That’s great info Animal, thanks. That makes a lot of sense.

So my Signal Path in this instance is the receiver’s DAC signal which might be explaining the differences I’m seeing in my Settings->Audio outputs in Roon, when comparing the Headphone Out output and the Optical Out output settings.

I’m guessing this is also why when I’m using the Headphone Out output in Roon I’m hearing the signal from the TOSLINK on my receiver as well, even though I’m not using that output in Roon. It was confusing me, but if the TOSLINK is just always passing that signal through, it is making more sense.

Right. And there are settings in Windows and/or the drivers for your sound card where you should have the option to turn off the TOSLINK when using the headphone output from the computer, but I am a Mac user and don’t know where those settings are and how to set them up. It is not hurting anything though.

Just for fun you can also try the headphones output from the receiver and see if you think it sounds better than the headphone output from the soundcard in your core computer. Any difference will be small but it is nice having options.

I’ve done some A/B testing between receiver headphone and soundcard headphone. I honestly find it hard to compare, plus I’m not on high end equipment, it is fun though.

I’ll try to find those settings, I’ve been through all those windows sound settings pretty thoroughly, there’s some bitperfect option in the clunky soundcard software as well. I’ll keep tinkering around, but thanks heaps for your input, it has clarified the issue for me.

cool, glad I could help! Yeah, tinkering is always fun