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Ahead Of The Game: Key Points & The Value Of Performing Needs Assessments Before Gigs

Having a step-by-step action plan along the lines of what's outlined here can help you sort through the stress of the live environment and make things go more easily and smoothly come “crunch time.”

In a recent interview, New England Patriots head coach Bill Belichick referenced the quote “Every battle is won (or lost) before it’s fought.” Love him or hate him, this saying rings true from skirmishes in football to an A/V production coming up in three weeks.

Plan A is to plan everything beforehand and try to set up as close as possible to that plan onsite. Plan B goes along the lines of “The events department person was an hour and a half late and I couldn’t even get into the building so I need to get the gear up and verified ASAP.”

An in-depth guide for the creation of a needs analysis, gathering customer information, conducting site surveys and evaluating a site environment is published in the CTS Exam Guide (Grimes 2013). It explains these concepts from the standpoint of the client being yours, and you acting on your own.

In this article, however, I’ll focus on what you could be working on if you’re already an employee of a company that does A/V production and assumes that the sales rep has already confirmed the event and created an equipment list. I believe this can also help freelancers. For this discussion I’ll focus exclusively on the sound system.

Getting Started

The first question I ask when I’m scheduled for a job is “Can I get a floor plan?” Sometimes the client or company will have floor plans for venues, and photos from previous years can help too. Other times the event is in a common ballroom, and most hotels have room floor plans available for download.

Floor plans are instrumental in determining loudspeaker placement and proper aiming to cover the room and/or specific audience area. The one shown in Figure 1 is to scale, which makes the acoustic modeling prediction easier. With floor plan in hand, here’s a laundry list of key aspects to address as fully as possible.

Figure 1.

“Is the floor plan to scale or do I need to do a site visit to take measurements?” This is the other option, manual dimension measurements with a laser measure.

Another way to prepare beforehand is with a Room Mode Calculator. Based on the dimensions of the room, an RMC can tell us where, in frequency, to expect a buildup of energy as well as where the soundfield is diffuse. For corporate events this is particularly great because it helps us preset our high-pass filters as a starting point.

“What are the makes/models of the loudspeakers that we’ll be using?” This is elementary but quite important. A prediction model can’t be created if you don’t know what you’re using and you can’t request substitutions if you don’t know what’s quoted for the job.

“Does the loudspeaker coverage angle fit the room or seating area?” This is more of the modeling stage; if you’re given free rule you can ask for something that fits the space. Other considerations are SPL capacity, active versus passive, rigging concerns and perhaps aesthetic considerations (such as white or black).

“Will the loudspeakers be placed in front of the microphones/stage?” If it’s a corporate gig, odds are they won’t be. Further, the highest ranking executive that you clip a lavalier mic to will be magically drawn to stand right in front of a loudspeaker and talk softly.

Related: “Will loudspeaker placement be compromised due to sightlines and/or aesthetics?” LOL! Yes. The Powerpoint slide show is the most important element in that room and don’t forget it. Every event producer would rather put the loudspeakers behind an air wall than block screens. Find out screen locations as far ahead of time as possible and adapt!

“Will delay loudspeakers be needed to ensure total coverage?” It’s always best to know when there’s still time to do something about it.

“Mono, left-right or distributed system?” This is often “dealer’s choice,” sometimes money decides. Separate feeds to loudspeakers result in a more robust system if there are any problems – redundancy is a good thing.

“Subwoofers?” They can add a complexity to a properly tuned system, especially in smaller rooms. Are they left-right or gradient subs? End fire or arc configuration? Do I have data on phase alignment between tops and subs (grille to grille)? Knowing this can help eliminate the need to use an analyzer to time align subs onsite, saving time.

“Rigging concerns?” Know the law, know Working Load Limits (WLL), inspect all rigging hardware every time before use. If you’re unsure about anything, consult someone who knows!

“Measurement positions mapped out?” Software prediction can be a helpful tool but it’s not reality. The work must be verified on site, and it needs to be done quickly. Make sure that all check positions are mapped out, namely: delay time, polarity/drive level/EQ, and sub-to-main time alignment.

I recently worked a job with pre-installed loudspeakers flown from the ceiling and was unsure what location received more level from them – the rear portion of the main floor seating or the balcony above it. I had to check both locations and compare to the mains, then set delay times to the more important area, which happened to be the balcony.

In Figure 2, each tag is a measurement mic position. Blue is to find delay times between the line array and some wall-mounted loudspeakers (not shown). Green is to find delay for line array and inner loudspeakers flown from the ceiling. Red and yellow are to check which area received more energy from the flown loudspeakers and to determine the delay times for the outside ones. Purple is the front of house location, where I wanted to determine which loudspeaker I was hearing most, then second most, and etc.

Figure 2.

“What console will I be using?” Odds are you know consoles better than the sales rep. They might know general aspects such as a desk’s capacity, but you know them inside and out, i.e., this one has more accurate delay settings, while this one has a Cat-5/6 stage box, and this one has the often-annoying “touchscreen” faders, and so on.

“Can I create a console file/processor preset beforehand?” Route and label everything on the console before it gets loaded into the truck and save that scene. Festival patches are great and you can use generic names for things. Some console platforms allow creating a configuration file on a computer ahead of time and importing it onsite.

Moving Along

The next phase is what I call the onsite portion. The first thing I consider is the timetable. “When can I get onto the dock on show day? When can I get into the room? When is run-through? When is the show expected to be ready? When are doors? When do I eat?”

Next up, electrical power. “Is it all wall power? Is there a distro and a tie-in? Do I anticipate grounding issues?” By the way, try never to load a circuit to more than 80 percent of its capacity. Pay attention to amplifier draw (watts/volts = amp draw).

One of the first things I do after arriving is to set up front of house as well as my analyzer rig. Once everything is set up, address routing management. If it’s a distributed system, you’ll probably want to put limiters on the output buses – sending clipped signal down the line is not good, with the addition of limiters giving you “one less thing” to have to think about while mixing.

Don’t forget to do a verification of each loudspeaker or element, then move along to the measurement positions – set delay times, sub crossovers, and with enough mic positions, system EQ to get to the target curve.

Now it’s time work on microphone EQ. For corporate events, the big goal is no feedback. (Automixer is your friend for panels of presenters with lavs.)

“Do I have wireless mixing capability?” Mixing on an iPad is great and sometimes you can even pass it off to another tech to mix monitors.

“What’s the appropriate stage volume? Are there SPL limits?” Dinner party? Keep it reasonable. Volbeat? Go nuts! SPL “police” can show up from time to time, so know how to make them happy. You do not want to be the reason a client’s event is shut down.

A great way to go with all of this is to put your needs assessment documents on a cloud service so you (and anyone else who should be in the loop) can access them any time and anywhere. Creating a template in Excel can be handy since you just add the variables for each show into the template.

Having a step-by-step action plan along the lines of what I’ve outlined here can help you sort through the stress of the live environment and make things go more easily and smoothly come “crunch time.”

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