Matt, I have read every post of this exciting thread.
Since you have the Overdrive, I highly recommend you speak to Steve Nugent about his 1.5m SPDIF cable with BNC terminations. He has done measurements that demonstrate this length, with BNCs, offers the lowest jitter. His cable is very competitively priced. I recently attended a Nordost cable demonstration for the Los Angeles Audio Society and had these facts independently confirmed by a vice president of national sales. The only other option I would trust is Oyaide BNC to BNC true 75 ohm cable, hard to find, and without Steve's support. Furthermore, in Steve's Audiocircle, you will find jitter measurements of his cable.
I hope you find this helpful.
I use a low fi Sonos connect into an Empirical Audio Pace Car with turboclocks and the Dynamo power supply into a modified (silver fuse, BNC input, Lundahl transformer) Metrum Octave. I wonder what it would take to improve on this setup significantly...Overdrive is really geared to the USB input (SPDIF is not reclocked, I believe). I read with interest in your input regarding the Rowland Aeris DAC. It is similar to Steve's Overdrive in so far as they both use an Analog Devices chip which provides volume control by varying the voltage. They both strive for an analog, non-over sampling DAC-like sound. Matt, could you be so kind as to elaborate on the differences between your old Aeris and your new Overdrive SE?
I want to thank you for creating and more importantly following up on this extremely instructive thread!!, Tom