Would like to mount speakers to ultralight titanium wheelchair any ideas?

its an ultralight titanium chair so it doesnt weight much. this gives me more to work with as far as adding weight. ive only got so much realestate to work with however for the placement so size is critical smaller the better but i dont want to sacrifice to much in sound quality. it should be a method with decent to excellent b so a subwoofer with good sound. ive looked into an all in one way of doing it but havent found yet one that looks like it will mount where it needs to go below the solid carbon fiber seat bottom. if you know of one that may work let me know. otherwise i guess ill have to mount a sub under and the smaller high speakers out the sides. it would be cool if i could have the option to add a syncronized led light kit to it. i suppose one of those square twelve volt batteries that are used to power things like lanterns and such would be a good choice for power unless somebody can thing of anything else. thanks for your time!!!!! -Weelz