Audio Basics: Not As Simple As They Look? Identifying & Solving Microphone Problems: Summary

Microphones are very important in studio recordings and live productions. Items that are important usually have issues. The microphone is no different than any other item that is very important. The article titled Audio Basics: Not As Simple As They Look? Identifying & Solving Microphone Problems, lists a couple of problems microphones can have and their simple solutions.

Microphones are transducers that convert mechanical energy to electrical energy. Whenever electricity is present there should always be a ground. As stated in the article, most microphones have a screw near the connector that is used to ground the handle of the microphone. If the microphone is not grounded properly, there will be a hum when the screw is touched. This can easily be fixed by tightening the screw into place. Sometimes an XLR connector’s shell is grounded which causes a 60Hz ground loop when the shell is touching a grounded surface. This is usually caused when the ground lug of an XLR cable is tied to pin 1. It is better to not connect the ground lug to pin 1. This will prevent the ground hum that occurs when the shell is touching a grounded metal surface.

Other causes of hums and ground loops are when mic cables are near or overlapping lighting and power cables. These cables create large magnetic fields that interfere with the signal passing through the microphone cables. The easiest way to get rid of the hum caused by overlapping cables is to just simply separate them. If separating them is not an option, make sure the cables are overlapping at a 90-degree angle. The cables can also be vertically separated to prevent the hum. The article also suggests using a microphone with humbucking coils if hum is produced when using dynamic microphones. It is also good practice to use Twisted pair microphone cables because they reduce the hum caused by strong magnetic fields. The better the cable is shielded the less magnetic interference there will be. The best types of shields for cables are the braided shield and double spiral wrap. Also check mic cables for proper connections at both ends.

It is recommended to make sure that all equipment being used has the same reference to ground. If two pieces of equipment aren’t connected to the same ground and someone were to touch them, they might receive an electric shock. This occurs because the two pieces of equipment aren’t sharing the same source of power. The solution would be to make sure the power being supplied to the equipment is coming from the same exact source.

These are the main and likely issues that microphones can have and their simple solutions. There is always a solution to a problem and problems happen everywhere, even with the innocent microphone.