24/96 SPDIF limit and 192/24 delivery via DAC?

Posted by: Dan43 on 03 March 2013

Unitiserve has both Toslink and Coax SPDIF outputs. I am not using a streamer but direct playback to an Amp via these SPDIF outputs (currently favouring the Coax with 75 ohm BNC)

 

192/24 playback hasn't been working, all 96/24 and under is fine.

 
A simple Arcam rLink DAC (or any DAC I presume that handles 192/24 delivery) solved it. Both the Toslink and the Coax can only carry 24/96 directly, it seems, but both work carrying/delivering 192/24 IF the DAC is connected.
 
The DAC seems to help bring 192/24 in and deliver it at higher res, I was told that SPDIF only supports 96/24 for direct playback but can transport 192/24 into a DAC, which then plays this out.
 
Basically is SPDIF limited to 96/24 for direct playback but can carry 192/24 to a DAC, which then plays back that HiRes signal? If yes then, as proved by plugging in the cheap Arcam DAC via Coax, then the streamers, which act as this carried/delivery system only really require a DAC.
 
Have I got my thinking right (Googling also) or is the Unitiserve SPDIF outputs limited to 96/24 and only carries 192/24 via DAC/streamer to deliver it?

Thanks
Dan43
Posted on: 03 March 2013 by james n

Dan - it sounds more like the DAC in the amp you are connecting the US to cant process a 192 stream rather than the US being incapable of providing it. You'll normally find that optical (toslink) is limited to 24/96 whereas coax will handle 24/192.

 

James

 

PS - what do you mean by direct playback. The US outputs a digital signal via it's digital outputs so needs a DAC somewhere between it and the amplifier.

Posted on: 03 March 2013 by mutterback

If you have a "direct connection" to the amp, there must be a Dac in the amp that accepts SPDIF in. So, I suspect whatever DAC is built into the amp you're using only goes up to 96/24. What amp are you using?

Posted on: 03 March 2013 by Dan43

Thanks.

I was looking from the wrong perspective. The amp can handle 96/24 according to its online blurb, but it is an older amp and probably isn't capable of decoding 192/24, something I didn't consider.

 

I was going direct to this amp from the US, and all 96/24 worked fine and 192/24 wasn't until I plugged in a separate DAC (Arcam rLink for testing), which is doing the 192/24 decoding job and delivering to the amp fine.

 

Good news, now I will be looking for a DAC/Pre or the SuperNait possibly as the next upgrade.

 

Best

Dan43

Posted on: 03 March 2013 by james n

Good stuff. Glad it's sorted