
There are tons of articles and videos on how to set up live sound systems, but how do you find a fault and fix a system? We can share the following tips gathered from years of professionals bashing their heads against walls and hope that they help you.
Although faults in a PA system can often best be found using measurement instruments, there are several things to consider towards fixing the fault before reaching for your test instrument.
first stay calm – blaming people or equipment will not solve the problem
if you have no stereo sound – probably the fault is post-mixer
be methodical – the shortest way isn`t the best -> follow each signal path, it`s better than checking components randomly
switch it out – consider changing multi-core channel, mixer channel with ones that are known to be working
Everyone has occasional problems with hum. Very often mains hum is caused by incorrect cabling of equipment.
Earth hum can be very difficult to isolate especially with very large PA systems. You can determine where the hum is coming from by unplugging all equipment from the inputs of your mixing desk and then plugging in each piece of equipment one by one. This method is very effective. Of course, the problem component will ALWAYS be the very last one you try – simply because you will stop looking after you’ve found the problem.
Good mixing!