What's the easiest way to regulate a 12 V battery to a regulated 12 V power source?
Preferably, I'd like a ready-made product so that I could avoid having to show my lack of skill with the soldering iron. :-) More complex answers are fine, too, as long as they are insightful.
I'm thinking of powering a 12 V / 600 mA stage piano/synth by replacing its AC/DC converter with a small car battery for portable use. Because the device is not designed for in-car use, I understand that regulation is the safest bet. (Of course, I could buy an inverter, but I'd like to "do it right" and get rid of the DC/AC AC/DC conversion.)