I noticed somewhat large upgrade in sound by upgrading my Modi to HRT MS II+. Now the 650's sound much airier and more "alive" than before. Now I understand why people say Vali requires a better DAC to claim its rights. Before upgrading Modi, I was determined to upgrade Vali first, but now I'm not so sure I need to upgrade anything in a long while.
So, you are using HRT MS II+ as a DAC and Modi as your amp ? or is the hirestech amp/dac ? I was planning to get Vali + Modi as my laptop set up to power my HD650's.. do you think it is not worth it?