Is this safe?

[SlashFortyForty]

To run keyboard through my Fender Bassman 100 (The older ones with 15" speakers)?

I wanted to use the drum machine on my keyboard to play my guitar along with.

[peeted]

should be, there will be much less transients out of a keybord than there are out of a bass guitar.

[moghes69]

bass speakers are generally made to be stronger so you should be fine. and also what peeted said.

[HaVIC5]

Yeah. Running anything through a bass speaker generally will be safe, if you can't find an all-purpose keyboard amp. It's running a bass through a guitar speaker that you have to worry about.