Gain Vs Volume?

[Aspiring]

Another way to look at it:

Gain and volume controls electrically do roughly the same thing. They both adjust the amount of amplification of the signal input to that stage. Both can impact the overall output loudness. But where they are in the signal chain changes how that impacts the final result.

The pre amp, amp, speakers and pedals and other circuits in analog components all have a designed operating voltage range for the input signal where they are optimized and as Doug mentioned where you get optimal signal with least noise. They all also have a maximum where they start to clip or distort.

Your various pickups and mics have varying levels of output voltage depending on how "hot" they are and how you play. The job of gain is to adjust the signal level (voltage
) for the early parts of your signal chain to achieve the right voltage to get the sound quality you are looking for from that part. So for example one pickup may put out 0.5 volts and another 1v for the same way of playing a note. Let's say the ideal pre amp output is 2v for the tone you are looking for. With guitar 1 you would set the gain to an equivalent of 4 and on the other it would be 2. Both times you would end up with a signal out of the pre-amp at 2v and assuming you didn't touch the volume you would get the same tone at the same sound pressure "loudness" out of the amp. If the amp is perfect by adjusting the volume control you would get the same tone at different "loudness". If however you change the pre amp control without touching the volume you will likely get a different sound to your tone also at a different loudness.

Higher gain can impact the output volume as well until you hit distortion then the output doesn't get any louder but only more distorted.

Tube pre amps and amps are much less linear than solid state and tend to have more differences in tone depending on where you are in the input range. As Doug mentioned the easy mode answer where things usually sound "best" is adjusting gain to just below where it starts to clip / distort on your loudest notes.

But, in some cases you get a better overall tone for electric on tube amps by turning the guitar volume down some and turning up the amp and preamp gain and volume as it lets the tubes operate more in the sweet spot. That's also the idea behind attenuators on those amps.

So the short answer is it depends on exactly what your equipment is, but a good starting point is to set the tone or sound quality you want with the gain and then adjust the volume to set the output loudness you want rather than what you say in your original of using the volume first.

[JKA]

If I understand things correctly, put simply:

1) set the gain on each channel so it's just below peak
2) adjust the volume on each channel to get the mix balance to how I want it
3) adjust the master volume to suit the room I'm playing in

Appreciate there are other factors/considerations but is this the basic concept?

[Chipotle]

Originally Posted by JKA

If I understand things correctly, put simply:

1) set the gain on each channel so it's just below peak
2) adjust the volume on each channel to get the mix balance to how I want it
3) adjust the master volume to suit the room I'm playing in

Appreciate there are other factors/considerations but is this the basic concept?

Yep, that's the basic idea. This, of course, assumes you have a simple set-up with mics/instruments going into a mixer, and the mixer driving speakers.

If you have more devices in the chain, like a guitar pre-amp or effects pedals, processors in between the mixer and speakers like an EQ, or even gain/volume controls on the speakers themselves, you have to make sure the input output levels on each devices are appropriate for the device itself and possibly for the next device in the chain. Getting gain levels correct at each stage is, as ljguitar mentions, called "gain staging".

[JKA]

That's great. Thank you everyone for taking the time to try and enlighten an idiot when it comes to tech. Yes, everything is simple in the set up. No add ons just plug in and play. 4 mics and 4 acoustic instruments. It's up to us to make it sound good...just need volume depending on the venue.

[Aspiring]

Originally Posted by JKA

If I understand things correctly, put simply:



1) set the gain on each channel so it's just below peak

2) adjust the volume on each channel to get the mix balance to how I want it

3) adjust the master volume to suit the room I'm playing in



Appreciate there are other factors/considerations but is this the basic concept?

Another key piece of clarification if you go this route. If you have two inputs in your mix and you have set the gain as above, and one is too quiet in the mix you have to decide between turning one up or one down. When you get too close to maximum volume in the quiet one you will need to turn the other(s) down instead or your quality of the quiet input will degrade.

And if the quality of the loud one starts to go down too much (if the volume gets too low in the dial) you may need to reduce its gain. It all depends on how close the signal levels are from all of your inputs.

[JKA]

Originally Posted by Aspiring

Another key piece of clarification if you go this route. If you have two inputs in your mix and you have set the gain as above, and one is too quiet in the mix you have to decide between turning one up or one down. When you get too close to maximum volume in the quiet one you will need to turn the other(s) down instead or your quality of the quiet input will degrade.

That makes perfect sense, thank you.

[Aspiring]

Oh one other bit if you have too much noise in one signal you may need to lower the gain and up the volume and try to improve the quality of the input.

Classic example is a microphone. If you have the gain way up and it's picking up a bunch of extra noise or feeding back then you want to reduce the gain and add eq or move the source closer to the mic to improve the quality and amount of the sound you want in the original input signal and reduce the amount of noise that gets in. But as per above that is only if the setting at just below clipping adds unacceptable levels of unwanted sound.

[shufflebeat]

Originally Posted by JKA

So...Once I set the gain I need to set the volume...then I set the master volume? If that's the case, what do I set the volume to?

Channel volume - *usually somewhere around zero, for a variety of reasons mostly based on the reliability and sensitivity of analogue faders,

Master volume - appropriate to the requirements of the venue/event.


*except for situations where you’ve set the gain appropriate to the preamp requirements but “fader at zero” results in a channel too loud for the context, for instance a hi-hat mic as part of a drum kit where the channel fader would be about -5.

[jseth]

Although there have been a couple excellent answers for you, I would offer this:

Google "gain staging" and read through it. Everything in there will help you with all your gear! The information will serve you well throughout your performing career.

[shufflebeat]

Originally Posted by jseth

Although there have been a couple excellent answers for you, I would offer this:

Google "gain staging" and read through it. Everything in there will help you with all your gear! The information will serve you well throughout your performing career.

Good call.

For more than you’ll ever need to know, but not too hard to follow:

SoS podcast - Gain Staging