there is another alternative that i would like to suggest which is Direct connection. just solder the LEDs to the speaker connectors and you are g00d to go... no hastle of amps or anything.. i have about 8 blue 0805 in my psp and it has been working perfectly fine for more than an year(i modded it last year) however, you may need some resistors since green leds funtion on less power than blue...
PS: they are perfectly sound reactive