[Slizzer]

So i'm buying this dac from https://www.jdslabs.com/products/48/o2-odac-combo/
Right now i'm customizing it, but there is a an option I don't understand, It's the gain option I don't know which one to choose: medium, standard or low.
 
I'm buying it with these headphones: http://www.amazon.com/Beyerdynamic-990-Premium-600-Headphones/dp/B0024NK34O/ref=sr_1_1?s=electronics&ie=UTF8&qid=1432278425&sr=1-1&keywords=dt+990+600
 
Can you guys help me decide what to choose ?

 

[DrKC]

I have the DT-990s in 600Ohm also.  I've had one of the amps (not amp and dac) from JDS to evaluate late last year.  The important thing with high impedance phones is the rail voltages of the amp.  The JDS can do about 15v rail to rail on freshly charged batteries.
It works well with the 990/600.  The 990 have a sensitivity of 96db spl ref to 1mW.  The 88mw spec of the JDS is a little close but it does drive them pretty well.  You can select the Medium gain.  That doesn't increase the power out per se, it just keeps you from having to turn the volume all the way up.  The 3.5 is plenty.
Good luck with your dac/amp and I hope you enjoy it.