Troubleshooting A Church Sound System
What are the best tips for troubleshooting a church sound system? When you detect a hum, echo, or feedback, there is likely a specific cause for the unwanted sound. To correct the issue, you may need to perform a series of troubleshooting steps, depending on the type of sound that you hear.
Hums are often caused by ground loops. Feedback is caused by the microphone picking up the sound that is sent to the mixer. Echoes are typically the result of sound waves bouncing off the walls. By identifying the problem, you can start troubleshooting potential solutions.
What Causes the Hum in a Church Sound System?
The most common cause of a humming sound coming through your loudspeakers is a ground loop. This occurs when two devices are separately connected to a ground circuit, while also connected to each other through a mixer. The current then flows in both directions, resulting in a noticeable hum.
To correct the problem, you need to determine which devices are causing the ground loop. Adjust the volume of all channels to 75%. You can then adjust the volume of each speaker and channel until you find the hum.
After you detect the device, determine where it is plugged in. If it uses a different grounded power outlet than your other devices, it is likely the cause of the hum. Simply use the same socket as your other equipment to eliminate the issue.
The hum may also be caused by a speaker that cannot handle the power coming from the output. If plugging your devices into the same socket does not solve the problem, try lowering the output level.
Besides a hum, you may also hear a hiss or a buzz. Buzzing sounds are typically caused by an audio cable being used to connect an instrument to an amplifier.
Audio cables intended for loudspeakers are typically unshielded, while instrument cables are shielded. The unshielded cable can cause this buzz, as you are using the wrong type of cable.
A hissing sound is often the result of mismatched input and output levels. For example, if the input signal is maxed out and the output is kept very low, you may hear a hiss. Instead of turning the output all the way down, turn the pre-amp signal down, and try to even out the two different levels.
What Causes Church Sound System Feedback to Happen?
Feedback is caused by a different type of loop. Instead of a ground loop, it is a looped signal.
Your microphone is picking up sound that is then sent to the soundboard. The soundboard then amplifies the signal and sends it to the speakers. When the microphone then picks up its own output, you have a feedback loop.
You may need to try several techniques to solve the feedback loop. You should try to reposition the microphone or the speaker responsible for the feedback loop. Ensure that the speaker is pointed at the audience. You should also check the position of the microphone to ensure that the pickup pattern is not facing the speaker.
You may even need to use a different microphone. If you use an omnidirectional microphone, switch it out for a microphone with a cardioid pickup. Instead of picking up sound from all directions, the microphone picks up sound from the performer or instrument.
If these options do not solve your problem, you can try to lower the speaker output so that the microphone does not pick it up. Another option is to lower the frequency of the input that is causing the feedback.
When all else fails, you can connect a feedback reducer or eliminator to your setup. These devices monitor the sound and automatically adjust levels to help reduce or eliminate feedback.
What Causes an Echo in a Church Sound System?
Echoes are caused by the sound from your sound system hitting the walls, floors, ceiling, or other surfaces and bouncing around the room. The sound waves reflect off these surfaces, creating the annoying echo.
There are several ways to eliminate echoes, including repositioning the speakers, removing digital reverberation, lowering the levels of specific frequencies, and adding sound dampening material to the walls.
You should first check the position of the speakers. If they are pointed at the walls or ceiling, they may be causing the echo. Ensure that they are pointed toward the church members and not the walls.
You should also avoid adding any reverb to your live sound through your mixer. While some performances may sound better with a little reverberation, you may add to the echoes with these digital settings.
A temporary fix is to adjust the equalizer settings for specific frequencies. By adjusting the frequencies, you may find that a specific frequency is echoing more than others. You can lower the level of this frequency to reduce the echoes.
If these solutions do not work, the final option is to dampen the sound. Wall coverings, curtains, sound dampening insulation, and padded panels can all help prevent sound from bouncing off the walls.
While you may not have the option of completely soundproofing your church, you can include covering in specific areas to help reduce the echoes.
Hums, buzzes, hisses, feedback, and echoes are common issues with sound systems. If you want to troubleshoot these issues, you first need to determine the cause. With a hum, the most likely cause is a ground loop caused by two devices using different grounded outlets with varying levels of electricity. Instead of using separate outlets, you should use the same socket.
Feedback is the result of the microphone picking up its own sound. Try repositioning the mic and the speaker. You may also adjust the levels of the mic or the speaker or use a microphone with a cardioid pickup.
Echoes are often caused by sound hitting the walls and bouncing around so that you hear the sound more than once. If you want to eliminate echoes, ensure that the speakers are not pointed at the walls or ceiling. You can also use sound dampening materials to keep the sound from bouncing off the walls.