Setting up a 66 blackface for bass

[robertneagle]

I have a 66 BF that I purchased about 25 years ago for $50. The guy I purchased it from knew nothing about the head n thought he was getting over on me. He had no cab to try it out on and when I got it home it didn't work. Had the transformer and tubes changed I think (it's been 25 yrs, can't remember all the details). Seeing as how it's been awhile I'm assuming it's time to have some services performed. What first? Aside from the occasional whack to stop an intermittent hum/noise (that seems to be caused by vibration and I think is due to a loose tube socket) I love this head for guitar as well as bass. However, when using with bass, when the volume gets above 4-5 the sound gets very distorted. Is this just the nature of these heads? While this feature is great for guitar, I want to be able to get all the power possible out of it cleanly. How can I get the most out of it for clean bass? Also, which parts is it safe to say would need replacing after 20ish years of neglect? I have some experience with electronics(intermediate) and I'm ok with a soldering iron. Please help!

[Tom Phillips]

Please tell us what model this is.
Bandmaster, Bassman, Showman or other?

[robertneagle]

Sorry, it's a bassman head

[loudthud]

The 50W Bassman heads are pretty limited as far as volume when used for Bass. You'll need a very efficient 4 ohm speaker to be heard in most situations. Most speaker cabinets sold these days won't get the job done except in resturants and coffee houses where volumes are low.

A cap job and some fresh tubes will make a noticable improvement in the sound, but don't expect any clean bass tones past 4 or 5 on the volume control.

[Raybob]

I use a '64 Bassman head with the 2x12 4 ohm cab and is fine for all bass gigs I get. If I need more volume, I use 2 15" black widows that fills any room. 25+ years, it probably just needs filter and bias caps changed and the pots and tube sockets cleaned.