I think the Amp helps fill in the bottom and mids better, but I don't think it's necessary. I've tried amping the 'phones twice. Once with the Fiio (and it was more than loud enough) and once with the LD I+ (and it was plenty loud with a lot more ooomph to push the bass and everything else). Though, I've yet to amp the signal since then and have had no problems using them and them being loud. You will end up turning the volume knob almost all the way, but on my MixAmp... after 80% it doesn't really get any louder.






















