The Daily Process – What is yours ?
At a recent show I had an interesting discussion with the house audio A1 who commented on how different some engineers process was when approaching a house rig. It occurred to me that surely most engineers did the same thing pretty much every show to check, tune and balance the rig for the best results for their show but apparently this is not the case.
It also made me think more carefully about what exactly was my process which is something that I have developed organically over many years working on shows.
So here is my process and I am very interested in any feedback that any of you have on how you do things differently.
First let me clarify a few things, I am an FOH engineer so most of what I have to say is about dealing with FOH audio. Nevertheless I think there is enough generality in these comments that there is something that could be applied to most audio engineers daily work process. Generally I work in larger theatres of all shapes and sizes, outdoor festivals, sheds and the occasional arena.
Usually I do not have the luxury of touring my own PA system and I am my own system tech (that’s a whole other story). Much of what I deal with on a daily basis is to do with the “PA du jour” whatever that may be and however it is installed.
Be Prepared
Before embarking on a new tour leg I like to have a whole bunch of information at my finger tips and a few “must have” items that I carry with me.
a) Advances
First off you need some specific paperwork that is issued as part of your artists contractual agreements. The major audio ones are a detailed input list and a PA specification, if you are relying on local providers. In addition your Production Manager will be detailing lighting, backline, rigging plot, backstage and dressing room requirements and more. It’s a lot of paperwork!
I discussed the audio related and other documents in a previous post (https://livesoundnow.blogspot.com/2023/03/ - it’s the first of two posts that month so scroll down until you see the March 2 – 2023 post)
Once the venue information starts to come in I build a set of folders on my laptop, numbered in order and named to correspond to each venue where we are doing a show. Once our Production Manager has done a technical advance with the promoters and various technical people at each venue he will copy the tech specs, drawings and any other necessary technical lists on Dropbox (or Google or iCloud or ????) so Audio, Lighting, Backline and Production Assistants can review the applicable files, lists and drawings. We often go backwards and forwards with questions and requests.
I download the relevant audio files onto my laptop in the appropriate folders. That way I always have access to the information even in difficult environments where there may not be any internet connectivity. Oh, and I read it all pretty carefully. Sometimes I may decide that the house supplied equipment is not sufficient or suitable and will go back to the Production Manager to discuss. It’s much easier to get stuff changed out a few weeks before a show rather than when you arrive at the venue. Hopefully, when I get to the venue each show day, I will know what the room is like, what equipment I’m dealing with today and will have an outline idea of how I’m going to handle it.
b) Carry with you
Several of the artists that I work with do not carry a PA rig when touring by bus and truck. We do carry a “universal” audio kit which includes FOH and monitor desks & racks, FOH multicore, stage monitoring rig, mics, stands & cable, AC distro and a personal kit each for the monitor engineer and FOH engineer.
My personal kit for FOH is a compact FOH rack with Com and talkback wired in a rack drawer, a laptop mounted in another rack drawer for multitrack recording/virtual soundcheck, an 8 input USB audio interface, and a DSP (my favourite is a Meyer Galileo or Galaxy). AC distribution, patch panels and an 8-way network switch round it out.
In a seperate cable case I carry measurement mics, clips and lightweight analysis cabling and a primary show laptop with Smaart installed. I also carry an ear monitor beltpack and spare ears for the LD so he can hear the cues that the artist whispers on occasion. That case also holds two sets of headphones, interconnect cables, spare XLR and power cabling, small surface lights, iso transformers, a semi-kit chair and a polar fleece jacket for those theatres that insist on freezing out the venue hours before doors!
The primary laptop also has walk-in music, any necessary pre-records or announces and controls both the DSP and the recording laptop remotely so I only have to deal with one control interface (other than the desk). If it’s a show that needs it I may also run a cue manager on that same laptop. I keep a fully funtional DAW program on the laptop for recording, playback, editing, ripping or any other audio tasks that may pop up.
This kit of gear, in conjunction with the desk (usually a Digico SD12) are my tools for handling whatever challenges the venue and the “PA du jour” have to offer and give me a chance of producing a consistent result from show to show.
c) One-offs
Sometimes we don’t get to carry a universal kit e.g. fly dates on a short tour leg or one-off corporates or festivals. In that case I have a baby Smaart kit (small audio interface, two mics and a personal laptop), a compact two track recorder (I always record the shows), headphones and minimal cabling. We’ll carry just a few essential mics and everything goes in our suitcases.
I have to say that it really helps to do a thorough advance so you know in advance what is in store and you have the necessary gear to get you through.
Show Day
i. First Look
Arrive at the venue, meet the techs of the day and do a visual inspection of the PA system. Does it look like it’s flown correctly, in the right location to cover the room top to bottom, toe’d in/out to your best judgement of the room. Is it what was specified in the advance? Are there other fills or delays that you can’t see.
ii. Get Started
Get load in sorted, power, rigging, stage locations for gear and FOH pushed out to the mix location.
iii. Do your own setup
Now you get to setup your personal audio stuff, patch and check that everything is working and normal.
iv. Connect to the house PA or PA du jour
Patch the interconnection between your gear and the PA system with the help of the A1, commonly it’s Left, Right, Subs, Fills and may often include a house program feed and other house specific requirements.
Discuss how to deal with fills, sides, delays and whatever other options there are in that particular space. You will want some control over all the PA zones and may have to lean on your A1 to help with delay time setting and basic eq if you can’t access each zone independently from your own DSP. Most modern systems have some kind of dedicated software or hardware to control the rig. On occasion these settings are locked off and you don’t get to change anything. In the past I have been able to persuade the house A1 to run an XLR patch directly to an amplifier from my own DSP when I have felt it was absolutely necessary to have control over a PA zone.
v. Validate the zones
Fire up some pink and validate your patch to the house rig and then check that each zone is operating correctly throughout the whole PA. This is a good time to get a feel for how the rig sounds, do Left and Right sound close to each other, how about subs, fills and delay zones, are all the speakers plugged in and in their correct zone. Should you leave the house preset curves as they are or flatten everything and start again (assuming you have that kind of time). Now is the time to do any physical adjustments you think are necessary, height of the rig, where fills point, adjust toe-in, whatever you think is necessary. You won’t always get your way but if you feel it’s needed then you have to try.
vi. Setup your measurement system
Once I know the rig is relatively OK and pointing mostly where I want it to be,
I’ll set up my Smaart mics, connect my measurement kit and start measuring. Of course I have a specific way that I do it and here it is. I’ll setup 4, 5 or 6 mics throughout the venue, depending on the size and shape, oriented relatively on axis of one main array.
#1 mic is in the main array coverage area close to the downstage edge (depending on the hang), #5 or #6 will be close to the top of the balcony or nosebleeds or close to the back wall, depending on the venue. One mic stays at FOH and the rest are distributed evenly throughout the audience area, usually in a line from downstage to the back of the house and in line with one side of the PA.
vii. Measurement first pass
On the first pass I’ll energise only the one side of the main hang and be very careful to make sure that any delays, fills or anything other speakers are muted.
Often I’ll adjust my interface to lay the curves measured by each mic directly over the top of one another. That will tell me very quickly what overall EQ changes I need to make and where there might be problems or more specific adjustments to be made. I use both FFT frequency response measurements and RTA measurements at the same time, if the coherence line is a big mess in one area sometimes the RTA can give you some useable average information. Interpreting Smaart data reliably takes a lot of practice and careful thought. Once I have an average house response that looks useable and sounds reasonable I’ll take a look at the phase curves for each location, just to see what is going on.
viii. Measurement second pass
Second pass for me is to check sub alignment with the main array. I will pick a mic that is in the middle of the audience area both horizontally and vertically as my reference position. This is often at FOH mix location but depends on the venue. Getting sub alignment right is tricky - see the Merlijn van Veen link below for a very detailed worksheet.
I will measure and capture the phase and frequency response of the main array, mute it and then do the same for the subwoofers. That should tell me pretty quickly if I need to delay the mains or the subwoofers to get the phase response aligned in the crossover region between subs and mains. Once that delay adjustment is made then I will check the same phase response at other mic positions. I may adjust the delay time to get an average that I think will work. There are a lot of gotchas with sub alignment, not the least of which is the “line of subs” across the front of the stage as favoured by several system manufacturers. (That configuration is non-alignable but the topic is way beyond this discussion. Maybe another time!)
ix. Deal with front fills
The next pass is to measure front fills. This needs a decision on how many rows of seats you think the front fills can, or should, or you want to cover. If your front fills are zoned in pairs, outer to inner, that means several measurements to get each zone aligned with the main arrays. The purpose of these fills is to give clarity and image location to the mix, they don’t need pounding bottom end and I high pass them quite agressively. I treat flown front fills the same way. Be sure to check relative phase response between the main array and each fill zone. It’s not uncommon to need a polarity reversal on the fills to match the phase response of the mains.
x. Outer and delay fills
Now the rest of the fills, outer, side and then, finally, any delays further back in the room. Again, look out for phase or polarity problems. Depending on seat sales (you did ask the promoter didn’t you!) I may consider not using any rear or upper delays for the show but I’ll still measure, delay and eq these fills, just in case! This is also the time to turn on the other side of the PA and all the zones to see what happens to your average responses, you may need to do some further correction.
xii. Listening Tests
By this time I am usually about an hour to an hour and a half into PA tuning, depending on the complexity and size of the room and the PA system itself. Now it’s time for music playback. I have a few songs that I play every time I measure and I walk the room with one of them playing (on repeat). I walk the main floor and listen for coverage, how even is the response, zone levels and smoothness of crossover between main arrays and various fill zones. I’ll adjust as needed until I feel that main floor is OK and then head up to the balcony, nosebleeds or wherever else I need to go. Near the top I will listen for similarity of tone, how even the coverage is, overall levels and balance of delays. It’s OK for the edges and top of the audience areas to be a little soft, just make sure that there is coverage and that it sounds satisfactory. (See an earlier post in this blog about levels throughout the venue).
xiii. More listening
Now I should have a good feel for how the whole room sounds and any other tweaks I might need to make. If all is well I will play one more tune that has heavier bass and drums and an enigmatic vocal track that really shows up any mid range problems in the eq. Now I am probably two hours into this process and hopefully I am fairly satisfied with where the system is at. We are not entirely finished but I will have a piano tuner waiting to go to work and it’s lunch time.
Piano tuner at work - close look at mics and mic saddles
xiv. Line check
Line check, just to be sure that we have all the channels patched correctly, that they are clean and responding as expected. One thing about line check that I would like to pass on is that it is really easy to mix up microphones when checking, especially on a mic heavy acoustic type show. If you get someone to walk around going “check, check” with their voice then it‘s much harder to be sure you have the right mic in the correct channel. We get our back line guy to do the line check for us with a drum stick and a gentle tap on the body of each mic; a fingernail scratch of the windscreen can work as well. The tap or scratch is so confined to one mic that you will not mix it up with one that is close by.
xv. Soundcheck
This is a big variable and can be a real challenge depending on the music format, the band and everyone’s expectations. For example, the soundcheck for a band and orchestra is not the time to be setting levels, eq’ing or trying to get orchestral balances. Soundcheck will be show rehearsal, song by song, and you need to make sure your cues for solos, sections and events are in place while they are rehearsing.
The time to get levels, eq and balance for orchestral shows is during the inevitable early morning note rehearsal when the orchestra and conductor (or MD) get to play through the orchestral sections without the band.
One of my current clients uses soundcheck for new song development and rehearsal and may not play anything show related. Other clients do parts of two or three songs and then leave. So you have to have everything done and sound checked as best you can before soundcheck, if that makes any sense!.
After soundcheck it’s supper time ... whoo hoo!
xvi. Doors
Most shows have walk in music, there may be announces or video rolls or house advertising. You probably need to be there!
xvii. Show time
Now you get to do what you originally signed up for, mix the audio for the show.
What about “Throw & Go”
Now having gone through my process in excrutiating detail (for some I’m sure) we have to accept that many engineers don’t have the time, the inclination or the necessity to be so detailed. There are many who arrive at the venue, toss a favourite track on the system, turn it up really loud and twiddle with the house eq for a few minutes. Once that is done they move on, process finished until soundcheck, if there is one.
Some mixers are extremely talented and can make this work well and it’s difficult to argue with success. But there are drawbacks to the “throw and go” approach.
a) You can never assume that the house PA or “PA du jour” is meticulously designed, installed or tuned, even when done by the manufacturer’s rep. It may have been setup with an emphasis on a centre array for Broadway style shows which does not usually work so well for music shows. It may have been moved in and out multiple times and who’s to say the box angles, trim heights, gains, eq and delay adjustments are the same as the original installation, if that was correct to begin with.
b) Coverage problems are not so obvious when the music is loud, there will always be audio everywhere. If you have a quiet show, speeches or theatrical performances then in the areas where the coverage is not correct people will not hear the show. If there are timing and equalisation problems then the content may be garbled and unintelligible.
c) Phase and timing issues can severely impact intelligibility no matter what level the program is mixed at.
d) Depending on how the PA system is installed the level, eq and clarity may vary a lot from section to section of the venue, if you don’t measure you don’t know what is going on in the rest of the room.
e) With talented mixing throw and go can get great results at the mix position and sometimes through the whole venue, it really hinges on how well the installation and tuning has been done, by someone else. Making these results consistent from show to show is much more challenging when you don’t really know how the system is really working and is different every day.
If you are interested in exploring some of the approaches that I have outlined in this article then here are some helpful links to articles and videos that give much more detailed explanations of what has been touched on,
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Interesting Links
Becky Pell’s excellent process for tour planning.
Rational Acoustics Training videos.
Smaart is really the king of analysis programs for working audio mixers like you and I. It’s fast, reasonably flexible, easier to understand than most other software and has a tremendous support and training program. This link is the best place to start.
https://www.youtube.com/playlist?list=PLbQ6rmufsxd7gk8N25gtjfPS_E2494Vwm
John Murray’s methodology for array measurement
https://www.prosoundweb.com/exploring-converging-techniques-for-tuning-line-arrays/
Howard Page’s detailed approach to large array tuning.
https://www.prosoundweb.com/tuning-optimizing-large-scale-concert-sound-systems/
Merlijn van Veen’s spreadsheet on sub layouts, design and alignment processes.
https://www.merlijnvanveen.nl/en/calculators/28-sad-subwoofer-array-designer-en
Interesting comparison of measurement microphones at different price points
One of the more practical lists of tools and stuff that an engineer might want to carry
https://www.soundnerdsunite.org/live-sound-kit/
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© Clive Alcock - 2024