There is a battery compartment on the back of my guitar that is opened by removing two screws and you simply swap batteries . No removal of strings is necessary .
If I claim to be a wise man , it surely means that I don't know .
as the active pup preamps are very probably class A (all amps have classes, not just power amps), two other things are more important than playing time: plug-in time (KR2 says) -- cuz once "on" the pups amp draws about the same from the battery whether or not you play, and shelf life of the battery - used or not batteries slowly fade. it is possible that somebody is finally using advance power supply and control techniques (available in integrate circuits for most CE products) in the highest end designs. (any one know?) but other than for voltage doubling (dynamic range and piezo pup plus), I doubt it, as it costs money in the design, and the biz guys will say to engineers, "save the 89 cents per pup -- let the tossers change the batteries."*
your best bet and value -- assuming you are religious about unplugging when not playing (we can't help you there) is a Lithium technology battery. you will probably get at least twice the actual "on" time - if not more, and v v good shelf life as compared to alkies.
*actual urinal conversation overheard in the loo of famous active pup company.
-=tension & release=-
They last absolutely aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaages. Had one in for at least a year n half, probably over 2 years. I started to think that the battery HAD gone but I didnt realise. So I looked on the EMG website n they say that you'll know when a battery is going because the sound'll keep cutting out or being choppy - that never happened to me. I still didnt beleive it, so I replaced the battery anyway. Sounded no different. So clearly the batteries really do last that long.
Actives sound the best in TODAY's music...because most studio guitars are played through the board. The reference to "phantom" power refers to what you'd get if you put a meter on the output...which will show it to be "zero"...but it isn't.
Geez! Batteries can be recharged or bought in bulk, duder!
Cat
"Feel what you play...play what you feel!"
