I recently got this 1x18 for free from a friend. Hes had it for many many years as its looks can show you. I have no clue what this could be, or is, and would like to know. My brother has been using it for guitar and he says it sounds really clean and works fine, but I dont want to blow it trying it with my bass. I dont even know if its a bass cab, but I think its safe to assume because its an 18... If you know what this is, what is the impedence of it?