Alright, so there's this bass on ebay. It's a yamaha BBG5 5 string bass. It's a sunburst color. My first question, why do yamaha's have that battery slot in the back for a 9 volt battery? I have seen it in many yamahas i have looked at. Also, what is your general opinion on yamahas if you have played them? i don't know if they have a good sound or not. Please help, this ebay item ends soon! Thanks.