[Gomoo]

Hello,

I´m thing about to buy a cmoy to drive my HD600 and in the future the DT 770 (250 Ohm or 80 Ohm). For which op amp should I look for?
Do you have any suggestion for any other cheap amp?

Thanks in advance!

 

[FallenAngel]

Absolutely - just use an opamp that is as close to rail-rail voltage swing and use 2x 9V batteries, you'll be good to go.

As for opamps that swing close to rails:
AD823 (best behind a simple buffer - like in a Sijosae Class-AB amp)
AD8066 (good choice overall)
AD825 (single chip, need to put 2 on a single-dual adapter)