Hey, I have question, would it work if I ll buy bass preamp and bass cab and plug it to valve electric guitar amp (as a power amplifier) ?
Or it's not best idea and I could damage amp ?
yes that would work. But I would only do it if the amp has a FX loop then go Preamp>FX return>amp speaker output>bass cab
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
I dont think you would have an issue with it working or not but even the most powerful guitar power amps are like 100 to 200 watts which can be rather low for a bass guitar. You may not get a usable tone.
I've been imitated so well I've heard people copy my mistakes. -Jimi Hendrix
You could but quite frankly, there is not much point. If it's a nice sounding amp, you could get an external equaliser and not bother with the bass preamp; most of the tone is from the preamp, anyway. Really though, you're better off just getting a low-cost bass amp.

"Show me war; show me pestilence; show me the blood-red hands of retribution..."
Last edited by eddiehimself at Jan 26, 2013,
It depends on the amp. Many of the best guitar amps are practically the same as old bass amps. But keep in mind that it usually has to be a good amp. The same qualities that make a bass amp good are the ones that make a good guitar amp. The guitar amp should also be more vintage-voiced and shouldn't be too gain-heavy. The main thing with using a guitar amp for bass is headroom. Unless you're using something really powerful, you probably won't get a clean tone at certain volumes. But most players who use tube amps don't play them for the cleans. You probably won't be happy with the results unless it's what you're looking for. If you do try it, I would just use the amp's preamp and skip getting a bass preamp. The bass cab will make things considerably darker. Nothing will be damaged though. The only harm you can do is to your wallet and back if you end up like tubes a lot.
You don't even need the preamp, as long as you have a bass cab and all the usual amp stuff like impedances are sorted then you don't risk breaking stuff, you just don't know how it'll sound.