So many schools of thought regarding Live Mixing - My brain is overloaded

I've been so frustrated with different schools of thought on live mixing. FIRST SCHOOL OF THOUGHT: The board mfrs (Mackie, Tascam, etc.) tell you to start with everything at zero. First adjust your gains (line/mic) to pre-clip, adjust your master fader to "0" and then adjust your channel faders. In other words, they are saying "Peak the Source". Then adjust your power amp for proper volume. SECOND SCHOOL OF THOUGHT: The amp mfrs (i.e. Crown, QSC, etc.) say to crank your amp volumes all the way up since they only control input to the amp, not output and to adjust the gain, channel and master faders at the source (mixer). In other words "Open the flood gates". I don't agree with the latter and I think that's old school. I can understand if you aren't in control of your amp, you don't want some musician coming along and cranking your volume levels and potentially blowing out your PA speakers. Another issue I have with the latter is that my mixer (Tascam 164UF) puts out to the DAW (Sonar 8.5) post-fade so If I don't peak my source, I get a very low Db recording. Can't raise the gains in the software high enough (+6 at max). Now, if that isn't confusing enough for you, lets match PA speakers to amps. They say a good rule of thumb is to choose an amp that is 2x the continuous power rating of the speakers at a specific ohm so you get enough overhead with a clean (non-distorted) sound. So, in my setup I use a Crown XLS 1500 that puts out 350W into an 8 ohm load. My Peavey PV115 are rated at 400w Program (continuous) @ 8 ohms. So the rule of thumb doesn't work here, I have plenty of overhead, would never be able to overdrive/distort/destroy my speakers. Maybe, I'll grant you, I'm underdriving them a bit. It's amazing how the levels of my amp never exceed 4 on a 1-10 scale and put out 95db's at 20-25 feet. Everything seems to be a "Rule of Thumb" and the "Schools of Thought" are what people have been conditioned to think (taught by others). OK, here's your time to chime in here! 

I have seen this before. I also came across a situation in a venue once where the power amp was cranked up full but the mixing console had to have the master faders right down and the channel faders down too. This resulted in two things. Firstly the metering on the mixer was so low it was useless and the resultant output was noisy as well.

I dont understand why amp manufacturers say to crank their amps up full. How would they know what is driving them, so it is a ridiculous approach and a stupid statement.

What I do anyway is start with power amps off, or turned all the way down. Put your master faders on the mixer at 0 db or unity. Bring up channel 1 fader and put its fader to unity or just under, (make sure channel eq is flat) turn channel 1 mic trim fully anticlockwaise at the top of the channel. (do this to all channels ie reset the console)

Then when the musician is giving you the signal on that channel, simply adjust the mic trim gain right at the top of the channel for roughly the correct signal level appearing at the master faders or the main mixer output. Maybe not right up to 0db here but set for about -3db or so. Plug phones in and listen to the signal that is coming in.

Repeat this for all channels one by one. You have now set the gain structure correctly for each channel. Some inputs are going to have lots of gain added eg dynamic mike and other hardly any gain ie synth output etc..

Now pull all your channel faders down. Get the band to play. Start bringing faders up again until you get the desired mix. You can turn the poweramp up to a suitable level here at this point but not fully clockwise though.

What you should be aiming for is a nice mix and with everything in, the master meters on your live console should be just peaking Odb. There should be NO overload or red lights anywhere. No different to a studio console. (analog or digital) You will find many of the channel faders will be around unity for a good mix. If the signal on the main meter of the mixer is starting to overload then bring all the channel faders down say 2 or 3 db or retrim any (or all) of the input mic gains to suit. A good trick is to set most of the channel faders to close to unity and set the mix of each instrument using the channel trim controls right at the top. Then you will have the most range of the channel faders available to you.

Now simply set your power amp for the desired level in the room. Those power amp controls might be close to being up full or maybe not. The signal levels should be correct in the mixer first. The myth here is that power amps don't sound their best unless their volume controls are up full. The level controls on a poweramp are designed to match the incoming signal applied for the desired volume out front. If you want to turn the music up then do it on the poweramps or the processor connected between, not the mixing console. (or you have 6 db or so up your sleeve on the console but not a lot)

Sometimes you can do what I suggest above for the mixer and have the poweramp input controls up full but only if there is something patched between them like a FOH EQ for example. Fine tuning of levels is available on that processor often. But if the mixer is feeding the poweramp directly then my approach works well.

This is also a technical issue and there is really only one way or the right way to do it correctly. It is not a what works for you situation. That approach might work in terms of what order to connect guitar effects for example. ie more artistic approach.

Also I am sorry for not giving you any advice about your recording levels in the DAW situation. That is another story all  together. I was mainly concentrating on the live mixer.

As far as actual practice....

The mixer and outboards turned on first..... after 5 to 1o seconds the amps are tuned on with the volume all the way down.  Slowly turn the amp volumes up to FULL.

Shut down is reversed.... amp volumes down, shut off the amps, then shut down the mixer and outboards.

doing it that way preserves the speakers.  Running a limiter on every live system is also advised. A limiter protects the amps and speakers from such things as mic drops and pyrotechnic mishaps.

Why turn the amps up to FULL? This allows the amps to work with their designed maximum headroom. Nothing gets clipped unless it's coming from the mixer that way. The amp should, of course, be matched as close as possible to the speaker load in ohms and power handling.  So running the amp on full will not blow the speakers but will in fact allow everything to work like it's supposed to inside the envelope of design. Doing this ensures the cleanest sound free from distortion.

Our band would turn the master up close to 0db  and adjust the individual channels for a good mix during the sound check.  Most sound techs learn that nothing is carved in stone. the balance between master and channels is fluid and changes from location to location. Some clubs required us to run "wide open" to get a good sound and others we had the master levels down substantially and the sound was as good as anyone could want.

Our sound check started with the drums. Getting a good balance on them. Then since we were a 3 piece band, bass and guitar next with the vocals. Adjusting as needed to get the sound right.

A house band I was in... 6 piece with 3 1/2 singers, 2 guitars, bass, keys, and drums.... we cheated I guess.... after a few weeks in the gig, we had the sound fairly well dialed in. So at the end of the night, the sound tech simply pulled the master to zero, and covered the board. Next show..... a sound check was a quick process of turn everything on, increase the master, and see if anything was out of adjustment. 99% of the time, since no one was in the club all week, and the equipment was covered up, all the settings were exact from the last performance. I understand that traveling bands do not have that luxury.

That's my take on it, how we did it in a few of the bands I was in.

I should have clarified to what situation I was referring. It was definately a situation where the components were not well matched or when the operator was having difficulty getting the correct signal flow within the desk as the front system was somehow preventing that. So there is no harm in turning poweramp levels down if it required to do so to get the best result out front. That is what the input level controls are there for. Any noise from the mixer will also be attenuated so it can improve overall signal to noise ratio.

In an ideal situation the poweramp levels are up full and in many situations where I have walked into a well designed system to mix, that was the case.  And as Mike mentions there are situations where the poweramps have no input level controls at all. This is a well designed setup when the mix is just peaking Odb on the master mix the volume seems to be just about right.

When the level controls on a poweramp are up full it means the spec is correct for the input signal level  to achieve maximum or the specified level of powerout.

Of course unity faders is not the aim just mostly in a good position to allow for all those changes that do ocurr in any live performance. In fact I do not mix with the mic trims at all. I only make minor adjustments on those. Here is a technique that works for me. Some channels on your mixer have constant settings all night and those faders are good at unity. You get a nice range above and below for fine tuning but at a glance you can see which these more constant channels are. I might fine tune those buy adjusting the mic trims on those channels more often. But other input signals are much more variable so aim to get the correct mic trim gain structure (then leave it alone) and then use the faders more during your mix. Visually you will also see more easily where things are in the mix. If you are lucky enough to get a soundcheck in the afternoon then you can get these gain structures set and if the band plays at night the same way you are set. And does not deviate too much through the night. It is always hard when you have never heard or mixed the band before of course. Then anything goes.

Thanks Herb for the reference to the switch on procedure. Very important! I thought the system was already on Another good reason to use the input level controls on a poweramp and only if they are easy to get to as well. If the mixer is off and you are not sure what is going to happen when you turn it on (and I am guilty of some crackers!) then if they are down the speakers are protected.

Then simply get the mix happening and turn up poweramps to the desired level and with a bit of luck it will be up full.

Jeff Evans


I have seen this before. I also came across a situation in a venue once where the power amp was cranked up full but the mixing console had to have the master faders right down and the channel faders down too. This resulted in two things. Firstly the metering on the mixer was so low it was useless and the resultant output was noisy as well.

I dont understand why amp manufacturers say to crank their amps up full. How would they know what is driving them, so it is a ridiculous approach and a stupid statement.

What I do anyway is start with power amps off, or turned all the way down. Put your master faders on the mixer at 0 db or unity. Bring up channel 1 fader and put its fader to unity or just under, (make sure channel eq is flat) turn channel 1 mic trim fully anticlockwaise at the top of the channel. (do this to all channels ie reset the console)

Then when the musician is giving you the signal on that channel, simply adjust the mic trim gain right at the top of the channel for roughly the correct signal level appearing at the master faders or the main mixer output. Maybe not right up to 0db here but set for about -3db or so. Plug phones in and listen to the signal that is coming in.

Repeat this for all channels one by one. You have now set the gain structure correctly for each channel. Some inputs are going to have lots of gain added eg dynamic mike and other hardly any gain ie synth output etc..

Now pull all your channel faders down. Get the band to play. Start bringing faders up again until you get the desired mix. You can turn the poweramp up to a suitable level here at this point but not fully clockwise though.

What you should be aiming for is a nice mix and with everything in, the master meters on your live console should be just peaking Odb. There should be NO overload or red lights anywhere. No different to a studio console. (analog or digital) You will find many of the channel faders will be around unity for a good mix. If the signal on the main meter of the mixer is starting to overload then bring all the channel faders down say 2 or 3 db or retrim any (or all) of the input mic gains to suit. A good trick is to set most of the channel faders to close to unity and set the mix of each instrument using the channel trim controls right at the top. Then you will have the most range of the channel faders available to you.

Now simply set your power amp for the desired level in the room. Those power amp controls might be close to being up full or maybe not. The signal levels should be correct in the mixer first. The myth here is that power amps don't sound their best unless their volume controls are up full. The level controls on a poweramp are designed to match the incoming signal applied for the desired volume out front. If you want to turn the music up then do it on the poweramps or the processor connected between, not the mixing console. (or you have 6 db or so up your sleeve on the console but not a lot)

Sometimes you can do what I suggest above for the mixer and have the poweramp input controls up full but only if there is something patched between them like a FOH EQ for example. Fine tuning of levels is available on that processor often. But if the mixer is feeding the poweramp directly then my approach works well.

This is also a technical issue and there is really only one way or the right way to do it correctly. It is not a what works for you situation. That approach might work in terms of what order to connect guitar effects for example. ie more artistic approach.

Also I am sorry for not giving you any advice about your recording levels in the DAW situation. That is another story all  together. I was mainly concentrating on the live mixer.

Jeff, Been busy and haven't had time to respond to this post. The way you peak your mixer is spot on. That's exactly how I do it. I don't know where the MYTH comes from either about maxing the power amp controls out either. I was always taught to peak the source (mixer) without clipping and setting the power amp for the desired level in the room. When I use this approach, then all the DAW issues go away.  Thank you very much for your input.  Put's my mind as ease

Guitarhacker


It comes down to what works best for you..  Some things are good practice and are universal between the different theories and ways to do things.....

Read "Live Sound Reinforcement" which is a good book to have in your library. It has good advice in it.  The copy I bought (B&H Music  @ $50) also came with a DVD that showed step by step from setting up to the show.

Where did you purchase the book.  I'm sure I can find it online.

Thanks jstefani for your words. As I said in my first post I have encountered situations where the power amps were up full and obviously too high and the mixing desk was all running at low channel gains and low master gain and with it came more noise and I am sure the mixer did not sound as good as it could. So by turning power amps down and resetting the mixer for proper healthy nominal channel strip levels and nominal output level then the desk is going to be happier and sound better. Now the channel gains are up higher for the weaker signals where it is needed the most. You start to hear the sound of the mic pre and the channel strip more.

When this situation of mixer down low and power amps up too hig does arise it means there is a mismatch there. I have also been in many live situations where the desk was just peaking 0db for the whole mix and the volume out front was perfect with the power amp attenuators up full. So that is a good match I would say.

This sort of analog thinking does translate into the DAW world. But I think you need some sort of reference and that is where K system of levels comes into play. It creates (3) reference levels and you get back to thinking about the rms or average part of the signal and aim to keep those levels constant across tracks and channels. Let the peak levels vary. Most people keep the peak levels constant and have varying rms levels underneath. (in the digital world I mean)