Gigging is probably one of the most enjoyable activities a musician can experience. There is always something special about performing in front of a live audience. The sound of a crowds appreciation when you have just ripped up the stage with a great performance of your best tunes. There is just nothing like it. But what happens when things don't go exactly as planned? And what happens when things fail miserably? If you have ever gigged I am sure you are familiar with Murphy law: If things can go wrong, they probably will. I have had experiences like: amps blowing up, guitar strings breaking, stolen fuses in my amp, bad cords, out of tune guitars, etc … These things happen to all bands and what makes the difference between a professional and an amateur is how you deal with these problems. You need to do some preplanning and put together aa Musicians First Aid Kit. When a problem does occur, you will be prepared to quickly fix the problem and get on with your show.
Guitar / Bass Strings
Get at least one extra set for each guitar or bass you have at the gig. If you pop a string you will be prepared to replace it. Remember this golden rule for guitars and basses: Never step on stage without a properly tuned backup guitar or bass. If you have any problems with your main ax all you have to do is pick up your backup and fix the problem on your next break.
Get a complete second set of cords. This includes patch cords and mike cables.
Go through all of your gear and make a note of all of the batteries you use. Get backups for everything and make sure the backups dont sit and go dead before you replace them. Consider some type of preventative maintenance schedule so you can keep track how long batteries are in use and when they need replacement. Dont forget about the guitar tuner!
Again go through all of your gear and make a note of all the proper sizes of your fuses. Get some type of small segregated box and label the top with the current ratings for the fuses (1A, 5A etc …). Never put a fuse that has a higher current rating in your amp or gear. There is a reason the manufacture put that size fuse in your system. Never, Never wrap a fuse with tin foil to bypass it! If your fuses keeps blowing, you have a short in this gear and by putting a larger fuse or bypassing it all together you may completely blow it up which will will cost you plenty to repair. Also I should mention that by bypassing your fuse you run the risk of electrocuting yourself! Never under any circumstanceses bypass your fuses!
Get a spare snare drum. If your snares let go just replace the whole drum with the spare and repair your main snare at break. Bring many extra sticks. I played with a drummer once that didnt bring enough sticks to a gig one night. He had to play the last half of our set with a screwdriver! Needless to say he had to replace all of his drum heads after this gig! Bring some spare hardware and also get another kick drum pedal. Some spare drum heads are always a good idea and make sure to bring a set of tools.
What would happen if your main synth went out? Maybe you could program your second synth with similar sounds. I know it wont be perfect but it will get you through the gig.
Do you have a spare mic? If not you should pick one up. I recommend a Sure 58. They are not very expensive and are reliable for a great backup if not a main mic.
Since I dont play horns I cant comment too much however I can recommend that you think about what could go wrong with your instrument. What could you do if it failed during a gig? Again a backup might be a good idea.
If you use an amp in your performance and it fails what could you do? A small spare is a good idea. Guitar players can use a guitar processor as a backup amp and it can be plugged directly into the PA. Again I know this wont sound perfect but it will get you through the gig. Bass players have it easy if their amps go out. Plug directly into the PA. If you play bass you may want to consider buying a direct box specifically for that purpose. Same goes for keyboard players, plug directly into the PA with a DI box
Always have plenty of duct tape! This stuff can get you out of some major jams!
I have not covered everything that can go wrong with your gear at a show but hopefully this will spark some ideas of the things that you can do if your gear fails. Put together your Musicians First Aid Kit in some sort of tool box or fishing tackle box. If you are prepared when things go wrong at your gigs (and believe me they will) it is no big deal. If you are not prepared you will look like an amateur and remember you never know who is out in the audience watching. Good luck and happy gigging!