Unity Mixing Followup
I ran across some cool conversations happening on the Sound on Sound forum a few weeks ago in reference to unity mixing. If you’ve missed the various things I’ve written about the topic, there are links on the homepage of this blog to the articles.
I’ve also seen another forum where one poster blasted me and called me a moron for approaching this topic. It has been fun to see how literally some people take this whole thing and think I’m somehow saying you should literally mix your show from the gain knobs or advocate poor gain structure in your console or the rest of the system. QUITE the opposite. I run my console really hot because we all think the Digidesign mic pre sounds better when its hit pretty hard and the desk as a whole sounds great when you get up and go with it. I think some are missing the point of my suggested unity mixing completely, so let’s dive into this just a bit to hopefully clear it up.
The whole point of this discussion is to make the inputs well mixed while setting gain, rather than just blindly going channel by channel and setting each to maximum individual gain. It doesn’t have to be perfect but just get things in the neighborhood so you don’t have to run some faders -30 or -40 dB below others. This makes mixing monitors from the same desk (which we do at every Kensington campus) MUCH easier. In this configuration, the inputs are well mixed, so that the sends to the monitor mixes and FOH faders are (more or less) at the same place across the board, making adjustments for the band a lot easier. If I know the band well, I can often dial in their monitor mixes from the FOH board ahead of soundcheck and nail it with few, if any, changes needed. We’re still running the inputs as a whole as hot as they should be through the desk so let’s not get into the whole topic of maximizing digital bits in the desk and the like.
Another example… imagine trying to adjust a monitor send, pre-fader of course:
A) with a very hot input, therefore with the FOH fader pulled down a lot, and
B) with a low input setting, with the fader pushed nearly all the way up . . .
‘A’ will be very sensitive to tiny adjustments at 9 o’clock and
‘B’ will need large movements at 4 o’clock.
With a mess like this all over a big mix, the experience is not nice trying to keep the band happy with their wedges and that is what gets so many of our engineers in trouble!
Second, if you end up with a difference, for whatever reason, where one fader is sitting at -30 or -40 dB most of the time, you have a MUCH harder time mixing due to the same amount of travel for a 3dB difference at or near unity, now gives you a 10-20 db difference with every move (Or whatever it works out to on the board, but a LARGE difference). This makes fine tuning a mix really difficult.
That’s it. Does this help make the concept clearer at all?
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Introduction
My name is Tim Corder. I started this blog in February 2007 because there were so few of what I considered good church audio resources available at the time for my team. Fast forward over 5 years and I'm still at it, sharing learnings about the journey towards making audio great. I go through periods where I post a lot and other times when I don't. I'm thankful for the opportunity to share it all with you. Thanks for visiting! 
Great post, Tim. I’ve been reading your blog for a while, and really enjoy it. I find myself agreeing quite often!
This is a great point. In my experience, one of the biggest differences between a good mix and a poor, lifeless mix is the gain structure…the added control that a good gain structure allows (due to the precision of faders when closer to unity) reinforces the need.
Overall gain structure is an interplay between all of the different gain stages, so I did have a question for you: how hot do you run the master on your board? How does the output bus level on the Digidesign boards affect the overall sound (if that makes sense).
The philosophy I’ve found works best for me is to run all of the stages of the PA as hot as they ideally should be (console to PA processor to amplifiers) and then dial back the amplifier attenuators on the outputs if running things hot through the rest of the chain means the mix is coming out too big and loud into the room. That way, we’ve maximized signal to noise, digital bits, etc etc throughout the entire chain where it really matters to the “sound” and we can just attenuate the amps a bit if necessary without any other negative effects. I don’t think attenuating amplifiers can add the bad things to a mix like noise, distortion, or other artifacts assuming you are gain staged properly the same way NOT running a stage hot enough could do. Does that make sense?
The alternative (and there are others who use this successfully) is to run the amps wide open and dial back gain, if its necessary, somewhere else like the crossover output or the console output. Not my preference but it is another way to do it. If you can’t run the faders at unity and still have plenty of individual channel gain while also mixing them well, there is a gain structure problem somewhere else in the system. I can’t stand systems where I can’t drive the console hard because the system processor or amplifiers are set too hot.
So…in order to dial this in, I would set the faders near unity, build a mix with the channel gains also mixed well so that there is lots of level in the mixer, then dial back the amps for the maximum level I want to be able to push in the room through the PA.
Anyone else want to chime in either for or against this philosophy?
Hi Tim, I would like to chime in, I am a big proponet of running faders at or near unity, however, I much prefer to handle system attentuation with-in the loudspeaker management tool. I prefer to handle gain on the input side, thus allowing all the power amps to be wide open in order to give me one location for system gain. This methodology allows a great signal to noise ratio for the record feed as well as allowing other outside engineers who are guests from time to time to have all the throttle if needed. I hope this helps in the discussion. This is just somthing that I have found that has worked for me in a bunch of scenario’s. Thanks for the great discussions
I want to see the post where they called you a moron.
But, in all seriousness, I haven’t seen any of the guys I respect who don’t have their faders sitting around unity when their mix is up and happening. There are several benefits including higher resolution on your fader moves while mixing along with easier recall of your baseline mix.
One thing I’ll say, though, is this isn’t something I grasped right away because I wasn’t directly taught it; I picked it up from guys I respected. If you haven’t been trained to do this, it takes time to make it work, but I believe it will pay off in the end for those who master it. The digital side can complicate it a bit if you are trying to maximize console resolution, but I don’t know of any excuses to not do this if you’re in the analog domain.
I’ll also chime in on Matt’s question. I’m with Tim on running the console hot and attenuating at the amplifiers. I try and optimize the system so that the master meters on the Venue are bouncing around 0 dB RMS when we’re at the average SPL we like in the room.
Tim, how do you handle things now with your new d&b rig? I can’t remember if you are running digital into the amps? Do you know if you attenuate the d&b amps, does it do digital attenuation or does it attenuate on the analog side?
For now we still go analog from the Digidesign with a stereo left/ right that daisychains through all of the d&b amplifiers and the on-board DSP takes it from there. From what I remember reading, the attenuators on the amps are working on the digital DSP side of the chain. So in many ways its pretty similar to Jeff’s suggestion to leave the amps themselves wide open and dial back what you need to do at the drive processor.
I agree, faders close to unity is the way to go live.
I do end up using processing to control my system gain most of the time. This is partly due to the fact that many PA’s are powered boxes so it’s the only option and partly because it’s hard to be accurate with the gain knobs on some amps. Especially if you’re in a one-off show situation where you need to dial it in fast and don’t have time to tweak 20 gain knobs on the amps.
I run our Venue pretty hot, usually around +10 Peak. I like to keep it in the yellow on my output meters during the bigger songs. Dave, how do you run your Venue at 0? The last time I mixed in there it was all red lights! Ok, sorry, had to say it.
Hi Tim,
Wow I wish I would have found your website years ago. I have been involved with church audio for about 5 years and all this time I have been doing EXACTLY what you said not to do. And its strange because, being an electronics guy, ham radio operator, etc. I didn’t feel right to me. with my gain up past 12 o’clock in many cases and my faders looking like a single track mountain bike trail well below the unity point. Currently I’m involved with a church plant doing “Church-in-a-box” and we hold service at a children’s theater with a great sound system (tuned for voice however not live music) My bigist problem is trying to get a good mix from the enclosed sound booth. I have an open window but its still a big pain.
So do any of the principals you talk about with unity gain change depending on the board your using? (analog vs digital for example)
Thanks
John