Reply to Guitar Hero MOd

Hey guys I added led's to my midi guitar hero guitar. The string of 15 led's run off a battery pack that I hid inside the body. I tried wiring it to the usb power wires coming in to the guitar but the led's were to dim.. Does anyone know if this 5v usb power can be raised coming off the pcb to the string of lights? I was wondering if anything could be soldered to the string of led's to give it enough power to make the lights shine brighter? And if so can an electret mic element also be added as an audio sensor somewhere in the beginning of that string of lights to make the lights blink with the sound of the music playing? I know I can connect the wires to a speaker like I've seen in other threads but that isn't possible on the GH guitar..
Any help would be greatly appreciated..

Thanks