How to Set the Gain on Your Mixer

I have found that a majority of worship leaders and volunteer sound techs do not fully understand the purpose of that knob at the top of the sound board: gain (also called ‘trim’ or ‘level’).  They know that it affects the volume but aren’t quite sure how it is different than the fader at the bottom of the sound board.

Properly setting the gain on your mixer is foundational to excellent sound.  As a matter of fact, if you do not set it properly, you will never get the sound quality you so deeply desire.  It is much like the foundation of your house.  When not done the right way, it causes a chain of reactions in which the entire house eventually suffers.

Properly setting the gain on your mixer is foundational to excellent sound. Tweet Quote

What exactly is gain?

The purpose of the gain knob on your mixer is to regulate the amount of input coming from the audio device plugged in, whether it be a microphone or instrument.  Every audio device emits a different level of sound signal.  The gain enables you to normalize the signal so every input is on the same playing field before it moves through the rest of the sound board (EQ, aux sends, fader, etc.).  Think of it like a water faucet.  The amount of water (signal) carried through the pipe (input cable) has an output that is regulated by the faucet (gain).

Keep in mind, the gain affects everything else on the sound board, including the monitor volumes, EQ and effects.  So, although you should not be scared to change the gain, you should do so with caution.  Otherwise, you chance blowing out the ears of your musicians if they have in-ear monitors, or creating feedback problems if your floor wedges are set too loud.

How to Set the Gain: Digital Mixer

When setting the gain, the source of sound (whether it be a vocal or instrument) should be playing or singing at the level they will be during the service or performance.  It is common for a singer to be shy if you ask them to sing alone, so it may be best to set the gain while they are rehearsing with the full band.

As they are singing or playing their instrument, use the level meter next to the gain knob to adjust the gain until it is averaging around where the yellow and green lights meet.  For example, on the Behringer X32, gain should average around -18dB.

It is okay for the signal goes higher during the peak moments (i.e. when a vocal is in their ‘power range’) but it should never hit the red.  Red means distortion, and you do not want that.  Yellow is still safe, but just letting you know that distortion is near.

Bonus: Download the Gain Cheat Sheet

How to Set the Gain: Analog Mixer

Step 1: Set Everything Back to Default

If you are setting the gain on a channel that is running to external processing, such as a compressor or EQ, you should bypass them all before setting the gain.  Then, make sure that all EQ on the sound board is level (at 12 o’clock).  Finally, turn down the aux sends and the fader to ensure that feedback does not rare its ugly head.

If you try to set the gain without out first bringing everything back to default, your level will be skewed.  For example, let’s say you are setting the gain on a vocal which is running through a compressor.  If you have have the compressor set for the current gain level, bringing the gain up will appear to make no change to the level of the input.  But, in reality, the level is increasing but the compressor is pushing back down.  So you end up with an over-compressed signal that sounds absolutely terrible.

On a side note, it is okay to make minor adjustments to the gain without completing this step.  If you have to adjust the gain during a service or performance (which does happen), you obviously do not want to bypass everything, as this would make quite the distraction.

Step 2: Engage the Solo (also called ‘PFL’) Button

First, make sure the the Solo button is not engaged for any other channel.  You only want it engaged on the channel you are currently working on.  In case you were wondering, if your mixer says ‘PFL’ instead of ‘Solo’, it simply means ‘Pre-Fader Listen’.  Engaging this button will allow you to examine the level of input before the the fader.

Step 3: Set the Gain

When setting the gain, the source of sound (whether it be a vocal or instrument) should be playing or singing at the level they will be during the service or performance.  It is common for a singer to be shy if you ask them to sing alone, so it may be best to set the gain while they are rehearsing with the full band.

As they are singing or playing their instrument, use the level meter to adjust the gain until it is averaging around where the yellow and green lights meet.  For example, n most analog mixers, this number is likely to be 0dB.

It is okay for the signal goes higher during the peak moments (i.e. when a vocal is in their ‘power range’) but it should never hit the red.  Red means distortion, and you do not want that.  Yellow is still safe, but just letting you know that distortion is near.

Step 4: Reset Other Controls

Now that your gain is set, it is time to get your monitors, EQ and other audio processing back in place.  Don’t forget to disengage the Solo (PFL) button so the level indicator lights return back to their default state of letting you monitor the overall output of the sound board.

Bonus: Download the Gain Cheat Sheet

3 Additional Things You Need to Know About Gain

1. Gain is not a ‘set it and leave it’ type of situation.  The levels coming from instruments and vocals will change from time to time.  Maybe a vocalist finds their confidence and starts to sing with more volume.  Or, the guitarist may change the output level on their pedal which means the gain should now be turned down to compensate for the difference.  A host of things can change.  So, get in the habit of using the Solo (PFL) button to keep an eye on things.
2. You may need to use the ‘pad’ button to achieve proper gain levels.  If you are setting the gain for a drum mic or some other type of ‘high output’ instrument, you may find that the level is still too high even when the gain is all the way down.  Luckily, there is a fix for this.  On most sound boards, there is a button near gain called ‘pad’.  When engaged, it brings the input level down tremendously, enabling you to properly set the gain.
3. Always see gain as the first step in the chain of excellent sound.  The gain is what feeds everything else on the sound board.  If its not right, you are not going to get the desired result from your mixing efforts.  If it is too low, the weak signal will make for a subpar sound.  If it is too high, the sound will distort, which is even worse.  So, give the gain the respect it deserves.

Questions? Drop them in the comments below.