meh, I wish I could find a schematic for that amp, but as it is I am hesitant. 2 AA batteries (3.0V if run in series) is not a lot of headroom for driving the 701s, unless there's some kind of voltage step-up in the amp, which is generally not sonically preferred. Also, there are at least 2 caps in the signal pathway, something you should really avoid unless your source has DC offset. Even then there should only be input coupling caps; imo there is no excuse for having output caps in a portable amp.
I'd buy the K701s and save a bit more and get a Mini^3 (built by one of the local diyers on head-fi or headwize). Your source shouldn't have any DC offset issues (most modern sources don't) and just getting those caps out of the signal pathway, plus tripling the power supply voltage all go a long way to making that amp a much better choice for the 701s, imo. Plus, the Mini^3 is a fantastic amp, with an active ground topology and very good measurements for a portable amp... and the AC adapter plugs into the back so you don't have three cables hanging off the front of the amp while listening and charging at the same time... I'd think you should be able to get a Mini^3 built for something in the area of $150 - $200, depending on the builder and the options you choose, etc., although you can't hold me to that price... I built my own so I don't know what the builders are charging these days.
