Hi

It should work with a speaker intended for use with bass.  Whether the tones you get will be suitable or not I couldn't say, but for practice purposes it should be OK at the very least is you use clean settings.   If your amp is less than 12 months old, you may invalidate your warranty by swapping the speaker out, however provided you take care when removing and replacing the existing speaker and you use a replacement speaker of the correct impedance and power handling and don't cause any damage then it usually doesn't present problems.    When using the amp, personally, like any solid state amp, I would probably not try to run it with the volume turned up full for any prolonged length of time - this is true if I were using the amp for guitar too.  Used sensibly you should not have any problems.

Nick

+ 1 to Nick and fflbrgst,

While you probably won't cause any damage to the amp some of the effects on the Spider IV are not meant to be used with bass.

Overall, I have had a bit of success in the past using guitar amps for "gritty" bass sounds but you will not be able to the same low end response out of any guitar combo that you can out of a bass rig.

Thanks,

David

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