Outboard Equipment

GRAPHIC EQ SYSTEMS

Graphic EQ systems allow you to adjust different frequency bands.

It allows you to balance the room and the equipment that we are using.

SM58 microphones and the speakers would normally be used.

Graphic EQ is connected to the mixing desk. Outputs from the mixing desk is connected to the graphic EQ. XLR connected.

​​SMLXL

This is a diagram of how you connect everything. The PA system and the GRAPHIC EQ SYSTEM.

Noise gate and compression

Noise gate is used to isolate an instrument from the others.

Compression is when you use it to set the levels from being high and bringing them down.

Using compression in live sound brings a consistency to a performance.

BALANCED AND UNBALANCED CONNECTINS

XLR cable is balanced. A jack to jack commonly unbalanced, however a normal tip sleeve jack is unbalanced and a tapering sleeve jack is a balanced jack to jack.

Feedback is caused by a loop of sound from the microphone going into the speakers and back into the microphone. The more sound finds its way back into the microphone it will then gradually build up and loop. It’s a problem loop that you will have to manually fix.

The higher the microphone gain the higher the chance of feedback. This is because the microphone is more sensitive than it usually is. Use sound check to make sure that the levels for your microphone is at the right level.

The microphone technique form a performer will also have problems with how the microphone pics up the sound.

EQ can boost a signal so can the response of the microphone and speaker system.

RINGING OUT

PFL the mic channel and ask someone to talk into it, set a gain from this where a level reaches 0dB on the meter.

PFL means Pre Fade Listen

-Make sure the gain is correct to the performer on stage. The positioning could also affect the sound.

-Place the microphone on a stand facing one side of the speaker system around 3 metres away.

-This would depend on how big the room will be. You want to capture the direct sound from the speaker system, you also want the surrounding sound.

-Having set the speaker level, turn up the master fader until feedback starts , then quickly turn it back down to just below the point feedback occurs. You do this on purpose so that you can fix it and eliminate and feedback. This is why it is called ringing out.

NEVER TAKE YOUR HAND OF THE MASTER FADER!!!!!!!

-This is because this process is dangerous, you can lose hearing from this test and you can also break the speaker and cause a lot of damage.

-Starting with the highest frequency, flick the fader up and down to see if it feeds back (keep one hand on the master fader level of the mixing desk at all times).

-If it feeds back slightly leave it where it is but however if it feedbacks aggressively then you need to turn it down to stop the feedback.

-Repeat the process on all 31 of the faders.

-Once you have completed the process, you should chance minimized the chance of feedback.

​​SMXLL

This is the GRAPHIC EQ that is used in "SHREWSBURY COLLEGE OF ARTS AND TECHNOLOGY".

The controls on the bottom row is each individual frequency level.

RANGE

The amount of adjustments that the fader creates. It is typically set to 12. It will just make a different in the decibel level.

BYPASS

What does it do? It will bypass the graphic eq. you may want to do this to check if the effect is working. If it is not working then you will know straight away. This just bypasses the eq settings. Don’t turn it on though. Feedback will be caused if this is turned on.

LOW CUT

This removes the low frequencies. It will completely cut them out. It will get rid of any rumble from any instruments.