new DAC for Grado HF2
The HF2 has a big bass hump and any good, clean sounding DAC will show that hump. It's a big part of the character of that headphone
If you really don't like that bass, you probably don't want to get a DAC that will mask it. Try some EQ to reduce the bass first.
You could still get a better amp/DAC combo than the E10 (eg: ODAC and O2 amp) but it won't greatly reduce the bass from the HF2.