Higher End DACs

Dmance your findings seem strange, first you don't list any of the components you are testing. 

Second you have only optical going in or out is that an optical cable from the dac to the server? Or some ethernet to optical and optical back to ethernet device?

Also why would you expect there to be an audible difference between a Rasbery Pi or a Nuc, both of these should sound the same. The issue is which is the audiophile server that you used and how was it compared? 

Just because you deem something to be a "audiophile server" doesn't mean it really is, the exact test conditions of what you used and how you used it may shed some light that a: you are 100% correct and it is all RFI/EMI that we are hearing as the cultprits in helping create different sounds out of a dac or

b. Your testing methodology of conclusions are wrong, what was the level of the listening gear being used to test the sonic differences? If so how were you able to then 100% shield any output cable from allowing back in emi/rfi and therefore invalidating your findings?

Just because you have access to a really big faraday cage doesn't mean your findings are correct.

Just food for thought.

Dave and Troy
Audio Doctor NJ

@audiotroy 

I have Chord Hugo TT2 to headphones (or direct to Voxativs) isolated from AC noise on a battery and Toslink signal input. With such a configuration, nothing upstream should make a sonic difference, right?  The TT2 is impervious to input jitter, so why does a server make a difference? Please don't claim that that bits are 'better' in any way ...yet in open air any upstream changes can sound different, why?  If a switch or power supply or cable changes the sound but the bits are the same going into the DAC, what else could account for this? Hint: its all about RF noise.

My test server was a Baetis (circa 2016), my NUC is a 5i5RYK, my Pi has a HifiBerry Digi+ module.  My test equipment is my ears combined with a SignalHound BB60c to correlate measured RF noise in the signal and proximate to the DAC.

Ok BOomer.

Dmance, sorry no. Toslink is the least preferable way to get a digital signal into a dac, this doesn't validate your testing.

Toslink has limited bandwidth and doesn't provide for asyncronous data transfer which enables the dac to control clocking other rather than the transport. 

Asyncronous data transfer also sounds the best hence most high end dacs employ this technique. 

Also Toslink means you are taking your data from its native electrical form on the motherboard, converting to optical and then reconverting it back to an electrical signal.

Also Toslink does not allow for much higher sampling rates or DSD.

Lastly Baestis music servers range from a few thousand to very expensive units, in our tests a $16k Baetis got bettered by a $4k Innous server which sounded dramatically better. 

The less expensive Baetis servers may sound better than your two other units but if you were using Toslink from a Baetis you didn't hear the Baetis which sounds way better through its custom AES/EBU board which you didn't use, optical from a Baetis is going directly from the native motherboard which would not sound any better than a rasperby Pi or Nuc.

If you would like to prove your claims please come down to our shop where we have multiple servers and dacs on display.

Dave and Troy
Audio Doctor NJ

@audiotroy,

Dave,
I don’t doubt your experience of differences in sound quality - perhaps your DACs are intolerant of jitter. Yes,Toslink is synchronous and maxed at 192/24 but apart from that its the same as any other digital transport...from the motherboard, from a custom board, etc. If there was any digital error in the stream you would be hearing dropouts, pops and clicks. So, apart from their innate bandwidth and protocol differences, toslink, coax, USB, AES all gets the bitstream to the DAC with 100% fidelity ...at least to Chord DACs.
My comments regarding RF noise and Toslink was in the context of this thread (High End DACs) as a means to get data from source to my chord DAC without any conducted RF noise, which i am convinced is the big elephant in the room.
I was just at CanJan, I should have taken the extra day to come see you. I have other NYC trips planned soon, ive messaged you.
Dan