I'm getting the Sennheiser HD 700 and not sure which AMP + DAC combo to make it shine, anyone with good recommendations?
I like trebles and mid range mostly and don't care much for bass.
I don't know your budget, but why don't you try the HDVD 800 to start? It's about $2K, has an amp & DAC, is fully balanced and is a Sennheiser product. Additionally Crutchfield has a 60 day return policy, so no risk.
I found lack of synergy with Sennheiser own amps, i think Op's can do better for the price. Plus, the HD700 aren't difficult to drive (150 ohms)