Amp for small studio mixing & tracking (DT 880 Pro)

My current setup is:

DAC (E-mu) -> Analog Mixer (Yamaha) -> Headphones (Beyerdynamic DT 880 Pro 250 Ohm)

I’m mostly looking for clarity and limited coloring. Rupert Neve RNHP springs to mind but that seems excessively expensive despite the (mostly) positive reviews.