02 Amplifier

Will the 240v version of the 02 amplifier work for me? I live in the USA and just have standard plugs in the room I was planning on putting the amp in. If not, would medium impedance work for the 6xx headphones?

The 240v amp would require that you buy a separate power brick in order to operate it in a standard American outlet. You can probably pick one up on Amazon for about 10 to 15 dollars. However, the medium gain amp would probably be just fine for a pair of 6XXs you just wouldn't get the same level of volume but it's certainly an appropriate choice. Either way, there are compromises to be had, but neither is wholly detrimental.