Technical factors for buying the ideal headphones for Kemper

1 - Generally speaking, lower impedance headphones will produce higher volumes when connected to the same headphone output. For me, the 250 Ohm DT770s are too low in volume in some situations. But I do think that the Kemper can drive even 250 Ohm headphones to unhealthy volume levels - although I haven't tested this.

2 - Also generally speaking, open back headphones are going to sound better. They allow air to pass through their ear cups to the speaker element. This means that pressure can’t build up and affect your sound, and there aren’t little echoes inside your headphones. Many expensive high-end headphones have open backs because it helps them sound more natural and clear. I strongly prefer open back headphones for recording and mixing for this reason, and use a Sennheiser HD660S (150 Ohm, by the way) with my Kemper. Downsides of open back headphones can be: more environment / room sound coming in, and more sound going out into the room which can be annoying for others

Use closed back headphones for critical mixing when you can't have any outside noise interference. And not at high volumes (although sometimes I do crank it up while practicing). You get pretty much closed off from the entire world with closed back which can be a good or bad thing.