1 Hipbone 2 years ago Posting this here because I know Billy is the authority on all things tubes. I recently purchased a Vox ac10c1 with a Greenback speaker from Sweetwater. Love everything about this amp. I started hearing a faint rattle/chime from the power tubes when playing on the low e string. Called Sweetwater and they sent me a new pair of Groove tube El84s. This set sounds very different then the power tubes it came with. The amp is super brite now, too brite! it came with some cheap Chinese tubes that actually sounded good, they just petered out very quick.Anyway my question is... what are the best tubes for this amp?