CD Player used as transport

Every transport will have different jitter characteristics, and typically fairly high jitter.  This is the difference you are hearing.  For transports, only output jitter matters, nothing else.  You can lower this a bit by putting various treatments on the disk, but the simple and more effective method is to add a Synchro-Mesh reclocker in the S/PDIF cable.  This has several advantages:

1) lowers the jitter to ~20psec - only the most expensive transports achieve this

2) upsamples the data to 24/96 - this forces the DAC to select a better sounding digital filter internally further improving SQ

3) provides galvanic isolation - breaks the ground-loop between the transport and the DAC which lowers the noise floor

4) it is no longer necessary to treat the disks to lower jitter

Here are measurements showing the effect of the Synchro-Mesh on an Oppo transport:

http://www.audiocircle.com/index.php?topic=154408.0

It is highly recommended that you use the best S/PDIF digital cable you can afford for the output to the DAC from the Synchro-Mesh.  The Empirical Audio Standard BNC cable is $275 and will satisfy this requirement. 

Here are some jitter plots showing how much jitter is added by typical S/PDIF coax cables:

http://www.audiocircle.com/index.php?topic=154425.0

Steve N.

Empirical Audio

Jitter is our expertise.

I have an older Wadia transport since new and connect it to a Jadis dac by the AES connection also have a Shitt Gungnir M/B dac connected to a Cambridge Audio CDX transport by way of the rca. Do you feel your answer would improve either of my dac transport combos especially the latter. Cables used in both instances are Acoustic Zen MC2.

Definitely.  The Synchro-Mesh does not have AES/EBU in or out though.  It has Toslink and coax, BNC and RCA in and out.

I have AES/EBU interfaces in my designs, but I have found them to generally have higher jitter for three reasons:

1) higher voltage is required for AES/EBU than S/PDIF, so more energy is required to get a fast risetime

2) usually and additional buffer is needed to do AES/EBU right, so this adds jitter

3) there are no 110 ohm XLR connectors to my knowledge, so matching the impedance is a challenge.  Cables for AES are also more difficult to build and get uniform impedance.

You could get a good Toslink cable and an excellent coax cable like my Reference BNC for $499 and run both of these from your two transports to the Synchro-Mesh.  Then you can switch between them on the front panel and get the benefits of the Synchro-Mesh for both.  A single excellent coax cable would connect to your DAC.

Here is a good Toslink if you can use it:

https://btpa.com/TOSLINK-XXX.html

Steve N.

Empirical Audio

BTW, 30-day money-back, less shipping cost, no questions asked on the Synchro-Mesh and my coax cables. My BNC cables come with 75 ohm RCA adapters.

There are customer feedback on both on my forum:

http://www.audiocircle.com/index.php?topic=154039.0

----

Empirical Audio