Originally Posted by andyschaub
If you do decide to go with the WA7, I'd recommend upgrading to the Electro Harmonix gold pin tubes on the Woo website. Yeah, it's another $100.00; but the gold pins are richer and warmer sounding than the stock Sovtek's so would be a better match for the Sennheiser (at least for the HD800's, again, can't say that I've heard the HD700's).
I agree, and suggest the Electro Harmonix tube upgrade as well. I found that they also make the WA7 more lively and engaging in terms of detail once you hit the mids, and they definitely contribute some air and open-ness up top in the highs. In fact, I would recommend that people consider the tube upgrades as part and parcel of the purchase.
As for the OP's question, I found the DAC to be quite competent. It's not the best DAC I've ever heard - and I do think 32/192 is a bit overkill - but the DAC's performance never gets in the way of my enjoyment. I've never compared it to a Bifrost though.