# gain or faders?



## bluesmostly (Feb 10, 2006)

question for you sound savvy guys. For doing live sound I was taught that you set the gain levels at just below peak, then use the faders to control vol. 

I have recently been told that you could set the faders at 'unity' or 00, and then use the gain to set volume or level. That the L/R faders for the mains should also be set at 00. 

what is your 'input' on this one?


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## jbealsmusic (Feb 12, 2014)

The first way all the way IMO. Cleaner signal, plus it's WAY easier to adjust faders in a dark room.


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## Granny Gremlin (Jun 3, 2016)

I have heard of mixing via the gain knob vs channel fader. It's been a minority tactic in the (recording studio) mixing world for a while. I've heard the arguments and see no benefit to it, but do see some negatives. When it comes to live sound *I* would definitely not do this; gain sets the sensitivity of the mic, and buffers the signal - you should not be mixing with that because it will change more than just the volume level. 

As for master faders - unity is fine as a starting point on initial setup; take it up or down from there as needed (and you often need to - otherwise you have to adjust all the channels individually to get the same effect - asinine to work harder for no good reason and harder to undo).

Think about it from a workflow perspective as well: why would you create arbitrary rules for yourself that don't let you deal with problems? Its feeding back and I haven't figured out which channel it is yet, but oh no, I can't move the master fader down from unity to make it stop while I sort that out. And why mix with what are often the tiniest knobs located furthest away from you vs the nice long throw purpose-designed faders that are right in front of you and easy to check visually for relative balance with other channels?

That said it works for some people in terms of their workflow and process, so fine, not saying you can't, but that it likely won't work as well in all situations (live). More suited to studio work (but even then, personally I think it's ridiculous, but to each his own).


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## ronmac (Sep 22, 2006)

Here is how I do it a couple of hundred times a year...

1) Set master and individual channel faders to Unity or zero 
2) Adjust gain control to achieve sound pressure level required for show
3) Mix the show with the faders. Unless for some reason the channel starts to clip, there is no reason to further adjust the channel gain (and a lot of reasons not to).

Why would you do it this way?

The mic or line preamplifier stage is set via the gain control. This stage is generally non-linear and tends to become noisier as you reach the upper limit, especially on low end boards. Having all of the amps working in this upper range will create a lot more noise in the system and expose you to a much better chance of clipping.


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## High/Deaf (Aug 19, 2009)

I do the same as Ron. I start with faders at unity and do my first mix with the gain controls, not allowing anything to clip (if it does, I find more gain on the output). Lower gain levels are fine, I'm not worried about being to close to the noise floor and giving up dynamic range at this point.

Through the night, I adjust the faders as required to mix and keep an eye on the input strips to make sure none of them clip (fricken drummers and singers). If so, I lower that strip's input gain and possibly adjust the fader.


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## bluesmostly (Feb 10, 2006)

ronmac said:


> Here is how I do it a couple of hundred times a year...
> 
> 1) Set master and individual channel faders to Unity or zero
> 2) Adjust gain control to achieve sound pressure level required for show
> ...


Really excellent responses guys, thanks a lot. Can you explain what "adjust gain control to achieve sound pressure required for show" means please? I was simply taught to turn up the gain to max level before peaking. 

Sounds like keeping the gain at a bit of a lower level is a good thing. I have never had the L/R main faders anywhere near unity, for our smaller shows, I would think that would be really loud.


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## High/Deaf (Aug 19, 2009)

Where to get rid of the extra gain that you don't need. That's a good question - and there's probably a few different answers. Here's mine.

If the system is louder than I need (and it should be, in most situations), I give away a little gain at the master section (reduce the output sliders a few dB) and give up some in the input gain controls. If you do a large gain reduction at any one spot, you can be giving up a lot of headroom and getting close to the noise floor. IMO, better to do a little at each stage. And then use the master sliders to set the ultimate level through the night. The strip faders are just used to change the mix through the night.

On larger systems, you may have outboard gear to reduce gain as well, such as EQ, limiter/compressor, rackdrive/xover unit. It's a balancing act, and that's why there's more than one solution.


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## bw66 (Dec 17, 2009)

If I need to reduce overall gain, I usually do it at the power amp. I like to run the board fairly "hot" to keep the signal-to-noise ratio fairly high.

As far as setting gain goes, I do pretty much the same as Ron and H/D as I like to have the faders fairly close to unity. However, for vocal mics, I tend to set the gains the same (assuming that the mics are all the same) and mix from there.


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## Milkman (Feb 2, 2006)

I set the gain for all channels at just below peak and mix with strip and sub group faders.

It works. I have no problems with clipping.

I run the master faders at unity and the strip faders where they need to be.


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## High/Deaf (Aug 19, 2009)

Milkman said:


> I set the gain for all channels at just below peak and mix with strip and sub group faders.
> 
> It works. I have no problems with clipping.
> 
> I run the master faders at unity and the strip faders where they need to be.


But if you need to lose 15 dB, where do you take it out? The strip faders? The subgroup faders? The outboard gear or power amp? A little bit everywhere?


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## jbealsmusic (Feb 12, 2014)

High/Deaf said:


> But if you need to lose 15 dB, where do you take it out? The strip faders? The subgroup faders? The outboard gear or power amp? A little bit everywhere?


I treat the live board just like a mixing console for recording. I want a good clean signal that is hot enough to be heard (say -12B to -9dB; peaking no higher than -3dB, preferably -6dB). Individual tracks are mixed on the strip faders, which are sent to subgroups for group mixing, which then go to the mains for overall volume control. The power amp is pretty well always dimed.

In the event of a channel clipping unexpectedly, I'd just reduce the gain on that channel and bump up the fader for that track to make up the loss (assuming the volume was where I wanted it in the mix).


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## Milkman (Feb 2, 2006)

High/Deaf said:


> But if you need to lose 15 dB, where do you take it out? The strip faders? The subgroup faders? The outboard gear or power amp? A little bit everywhere?


If I already have a good clean mix with head room, bringing it down 15 db is easily done. I can just bring the cross over down or the main graphs.


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## bluesmostly (Feb 10, 2006)

we do our own sound for most gigs, which are usually smaller rooms with a couple of hundred at most, for larger gigs and outdoor stuff we have the sound done by one of the local sound companies.

Running the strips and mains at unity is stupid loud for most of the gigs we play. for now, I have the powered speakers at unity, I have been running the strips at around unity, with the gain at just below peak, and the main outs at whatever the room will handle. Would it sound better to take the input sources down some, and the gain and strips down some so I can pull up the house more to reach the appropriate db levels that way?


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## ronmac (Sep 22, 2006)

Keep the input gain (mic and line preamp stage) as low as you can and set the strips and master at unity or just a bit below. This method gives you the best control of each source and the highest possible signal to noise ratio through the mixer.


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## bluesmostly (Feb 10, 2006)

Ron, so the gain knob turned down below near peak? what does, 'as low as you can mean?" I was of the impression that you lose dynamic range and the sound (from mics and keyboards for example) gets muffled if the gain is too low. 

thanks for help.


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## ronmac (Sep 22, 2006)

"as low as you can" means to only use as much gain as required to feed the following stages with clean signal and adequate headroom to prevent clipping. 

But, it isn't the only way to do it (as described in the link below). I do it the way I do because it has proven the best method to get the cleanest signal through the entire chain and provide the most control over all the changes that may occur during a show. Having everything setup in a linear fashion means that all of the settings for any of my post fader processing/sends/effects won't need much adjusting regardless of who steps up to the microphone. Changing all of that if I needed to adjust the faders all over the place would be impossible to do. 

You may find that another method works better for you.

How to Set Gain Levels in Live Sound - Three Methods - Behind The Mixer


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## amagras (Apr 22, 2015)

What world are we talking about, analog or digital? On analog gain is good, on digital 0db is the absolute maximum.


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## ronmac (Sep 22, 2006)

amagras said:


> What world are we talking about, analog or digital? On analog gain is good, on digital 0db is the absolute maximum.


Explain, please.


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## amagras (Apr 22, 2015)

If the mixer he's using live is digital it would better to feed the converters with a maximum of -12 dB.
Apart from that mixes are done with the faders.


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## robare99 (Jan 9, 2012)

On my Presonus, 0db for the input gain is clipping. So I run my inputs at around -15ish. That gives me the headroom I need. I run my master fader at unity, by my channel faders fall where they may. I don't mix with my gains.


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