6 months ago I was asked to join a rock band that does a lot of newer stuff and some classic songs. I have played in bands for years as lead singer, lead guitar and keyboard. They asked me to replace their bass player who they fired. I have played some bass before but didn't have the equipment. I bought a nice Warwick Corvette proline from my brother who has 4 basses and decided to just use my keyboard amp which is a Peavey KB300 with 180 watts, a 15" woofer and a horn. It sounded pretty good with the Warwick but now has developed a buzz when I play. I took it in and the tech just told me everything was fine. I don't know whether to replace the speaker or if it's the horn making the noise and needs to be replaced. I have thought about just saving up and buying a new Acoustic B200H head and a B410 bottom. Any suggestions as to what route you would take?