What is the best digital interconnect

I use the Transparent Premium Digital Link. It's a coaxial digital cable. They sell for around $300. Transparent has an reference cable as well. I really like the difference it made in my Denon DCD 1290.

I have Illuminations Orchid, Synergy Designer Ref and Illuminations D 60. All are excellent, but they all sound different and I prefer different ones with different equipment combinations. AES/EBU and RCA also do sound different. I bet you could live with any of the tope end recommendations, but if you are going for the maximum out of your digital equipment you will have to experiment.

Give a listen to Harmonic Technology (www.harmonictech.com)Truth-Link (copper) and Pro Silway MKII (2-copper, 2-silver conductor), and Goertz (www.alphacore.com) MicroPurl (silver conductors, copper ground) before making any final decisions. Some of the major problems when system matching are impedance and capacitance of interconnects. These designs hit extremely low values in each category--a major plus. HQ sells only through dealers. Goertz (Alpha-Core) has a 30-day no-cost approval program. Both designs, I have found, are excellent.