Has anyone heard the 47 labs Shigaraki DAC?

This is more than a tweak; it dramatically changes the sound for the better. I don't understand how it works, but it certainly does. Yoshi recommends painting the wire with enamel, but the enamel has a tendency to crack off leaving the wire exposed. Also, you need to paint the wire a few times. The Canadian 47 distributor recommends acrylic paint in yellow or another easily visible color so that you can touch it up on a second coat. I heard a very nice system including the Shig digital gear and the Essence speakers with this "tweak." It was shocking. And we changed only one length of cable: the single run from the transport to the dac. With the stock wire, I noticed a sort of closed in top end and a little distortion in the highs. We changed the one cable, and it cleared right up. I couldn't believe it myself. I am going to do it myself once I get my act together. Good luck.

There is a review of the 4715 dac in the current (March) issue of Stereophile. I am not sure if this is the same dac as the shigiraki or not. But they appear to be similar.

Yup, that is the Shigaraki which is compared to the Sony 777 SACD player.

Kforton, nice tweek. I want to try it. How did you strip the insulation of OTA? With wire-strippers? heat? I cannot pull off more than, say, 10cm at a time.

Wire strippers. It's a tedious and dangerous job. It's a good thing 47 gives you 50 meters in the kit! As long as you make a clean cut through the insulation it comes off with just a little coaxing.