In my experience... most 9v batt actually have only 8.4v power. The worst is many off cheap and unbranded batt have lower than 8.4v, thats mean there will lower power to supply the amp which mean the output sound will impacted. Most amp have power swing for their power need, like my L3 is 24v up...

Woow 680mah!!! That will make the amp longer run. For the sq try maha imedion 9.6v, it give more power than other batteries. I used it for my L3 and really make the amp better sq..

I agree... Fostex and solo have their own sound signature, it depend on what we want to choose to hear... Back to pico, im sure now i really want to have it one :blush:

Very interesting amp... @ currawong, how this amp compared to your triadaudio L3? I have L3 and love it, but the battery run out very quickly. Im pairing my L3 with fostex hpp1 with iphone, mostly driving my T1 If pico as good as L3 im sure i will have one

For me my best transportable setup is iphone 4s, fostex hp-p1, triad audio L3 driving T1 or sony z1000. Im really pleased for the sound after trying other amp like national, rxmk3b, portaphile 627 even small desktop amp like gs novo