Get the most solid gear you can find and then pay attention to it and take good care of it. As far as what can hapopen on a gig... anything. Strings break, batteries die, controls fall off, screws loosen, hoardes of angry gerbils could nest in your cab, etc.
Until recently I pretty much always took two basses but not as a main/backup thing, just that I might feel like playing one more than the other. Recently I've started travelling really light, taking one bass. I check my basses out often so a potential problem isn't likely to go undetected. I haven't broken a string since the Carter administration. Because of how I play the chances of one breaking are extremely negligible. In any event I'm ready if it does.
Always have spare strings, strap, batteries if you have an active bass, cables, a simple set of tools and learn how to set up your bass. If you take your bass from one temperature/humidity extreme to another it can make your neck move to a point where it becomes unplayable. If you know how to adjust your trussrod, no sweat.
Be prepared is still great advice.
Until recently I pretty much always took two basses but not as a main/backup thing, just that I might feel like playing one more than the other. Recently I've started travelling really light, taking one bass. I check my basses out often so a potential problem isn't likely to go undetected. I haven't broken a string since the Carter administration. Because of how I play the chances of one breaking are extremely negligible. In any event I'm ready if it does.
Always have spare strings, strap, batteries if you have an active bass, cables, a simple set of tools and learn how to set up your bass. If you take your bass from one temperature/humidity extreme to another it can make your neck move to a point where it becomes unplayable. If you know how to adjust your trussrod, no sweat.
Be prepared is still great advice.

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