I intend to build a stereo headphone mixer/amp type device for mixing bass guitar signal and the output of an mp3 or cd player. The preamp will be a couple of TL082s or similar dual opamps (plus various stereo pots and filter circuits, etc), and for the power section my first pick was going to be a pair of LM386s. I was going to run it at 18V for the clean headroom, and I was going to leave the gain set at 20 instead of200 (pins 1 and 8 not connected).
IIRC, even in this state, the 386 is actually overkill for headphone operation, and it tends to consume a lot of power. I would prefer this device to be battery powered (so I can walk around with it wirelessly). Are there any newer, more efficient, or lower-powered-but-adequate-for-headphones type of chipamps that anyone could recommend?
Or is battery life just the price you pay when you want to physically move stuff with electricity?