I know I can, but I'm not sure it will work. Will I need a bigger battery? Right now it runs on 3 AAA (1.5 volts) each. The soundboard was gutted from a 2010 Hasbro Vader lightsaber. The plan is to upgrade the LED to a Rebel Star and add a recharge port with a 3.7v Li-Ion 2600mAh battery (18650). I was thinking that if I upgraded the speaker from a 0.25w to a 2w or 5w it would be louder. ( clearly my command of electronics is, impressive...least impressive. )