Since they're powered monitors (active), you're just using line-level output from the DAC (the E10) to send a signal. You're not losing quality by going from 3.5mm TRS to dual 1/4th TRS. You can get a 3.5mm male to dual 1/4th males for this no problem. You can also use 3.5mm male TRS to dual XLR male since your monitors have both XLR and TRS.
Cables you could use:
Also you can use your monitors and headphones at the same time doing this (the line out works all the time; and the headphone out works at the same time too; volume controls the headphone only). And this E10 lets you use headphones upwards of 300ohms without breaking a sweat, which opens your options.
Very versatile and powerful little device with a great DAC for a very attractive price.
Hey, so I went ahead and bout the E17 DAC. I bought the 3.5 to dual 6.3mm (but I got the adapter off monoprice). Unfortunately, I seem to get god awful sound quality with it. The E17 is known to be decent, correct? If so, do you think it's possible my adapter is just crap when hooked up to my monitors or is the E17 just not very good? It sounds perfectly fine with my Focusrite Saffire, but the saffire won't drive the headphones (hence why I purchased the E17)
For reference, this is the adapter I picked up:
Edited by Neotriple - 2/9/13 at 3:51pm