What is general consensus on the best matching DAC for this popular combo? Have the phones and amp on order, need to decide on DAC, budget up to $5000. My options so far are Lampizator level 4, Metrum Octave/Hex and Schiit Gungnir. 

Hi all, I'm currently using my iMac to listen to audio files via Schiit Bifrost/Valhalla + Sennheiser HD650 combo, sourcing audio from iMac's optical spdif minijack.  Now I'm all into upgrading my system to WA7 + Audeze LCD3, however I noticed that WA7 doesnt have optical SPDIF input, only...