I have a Devilsound NOS dac hooked up to a Mac (hey, that rhymed). I'm using a Millet Hybrid amp with it and listening with HF-2s. My ONLY complaint is the highs are a tad grating; I've broken in the HF-2s for many hours, and I'm thinking it may be the dac. Time to EQ a bit more. Other than that, I'm really happy with this setup