aksakhilFrom what I've read, people tend to suggest pairing a solid state DAC with a tube amp. That said, I'm using the aune T1 line out into my Crack with some beyer 880s/600 ohm. Sounds great of course, but I can't tell you any side-by-side comparisons regarding the D1. I bet if you stick with a neutral tube you'll have similar performance to a SS DAC. Then you can change tubes later on if you want to.