I have a Yamaha MG24/14fx mixer. I'm trying to figure out how to properly set the channel gain levels. I got the basics of it but am uncertain where the fader needs to be when I start the process. Do I need to have it all the way down to the bottom or set at "0"
I always start with mine set all the way down. But allow me to elaborate on this more.
Input Gain should be thought of as a tool to correct a problem. It can boost an incoming signal that is too weak to adequately drive the rest of the system and/or provide a healthy signal-to-noise ratio. Many microphones provide a very weak signal and need boosting. Some sources provide a very strong signal and need reducing (Padded). If the signal is too weak, you may be adding hiss to the audio due to the noise floor being amplified along with the signal. If the signal is too strong, it can easily become heavily distorted which sounds ugly.
You should use the gain knob to adjust the incoming level accordingly. Think of it as a mini amplifier which can boost a weak signal. Only add as much as is necessary to create a proper, usable, and optimal signal level for the rest of the channel strip and system processing. How do you know how much is enough? ...By making use of PFL meters.
Speaking of meters...here is how to best understand analog meters.
The 0 dBu reading indicates the level where signal-to-noise ratio is at its optimum. It is the loudest it can go without adding any noticeable distortion. As you increase level beyond 0 dBu, distortion is gradually being added to the signal. By the time the level hits the peak indicator, distortion is at its maximum and most noticeable. If the signal remains consistently below the 0 dBu, then later in the system, you may be amplifying the noise floor (hiss) unnecessarily. Thus, 0 dBu is your target.
The procedure to set gain should be as follows...
- Turn down the faders and any Aux sends. Also turn the Effects switches to Off.
- Turn on PFL and watch the 3rd meter.
- With incoming signal, increase gain until the signal frequently bounces around the 0dBu mark. It is OK if the signal occasionally goes above 0 dBu as long as it does not hit peak very often.
- Gain should be left alone for the remainder of performance unless the source level changes a lot and needs correcting.
- Set faders to desired level for the room.
- Lastly, set Aux Sends to desired level.