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I am often asked (as I was for this article) what the best microphone to use in a conference room is. My answer is always this: “It depends.” Just as with the selection of video or other AV components, one size does not fit all here. What follows is a guideline that I’ve created to help people make good choices with respect to microphones based on their circumstances and needs.
Best Microphones for Huddle Rooms, Smaller to Midsized Conference Rooms
Many choices are available for these applications. For practical and efficiency reasons, it’s probably best to stick to a single manufactured package of products for installation. Combinations of camera, speaker and microphone packages are available from many manufacturers, and they have been designed to work together with a video monitor of your choice. I’d also suggest that you choose one of the known, name-brand offerings, rather than being tempted to “trail blaze” on a set of conference rooms because you find one component that has a new function that catches your eye. In the event you have issues with a room, it’s much easier to get technical support from a single provider than it is to call multiple people to try to find out why a device doesn’t work as expected with another manufacturer’s product.
Please be aware that, even though the technology of microphone design has advanced greatly over recent years, physics still rules the acoustics of what is possible. For example, you still have to speak as close as possible to — and in the direction of — the microphone in order to be picked up clearly. You cannot turn your back to a microphone and be picked up at the same level as when you face it. I know that observation might appear obvious, or perhaps even harsh; however, I cannot count how many times I’ve been shown an array microphone and been told that this fact doesn’t apply to that particular product.
Suggested Microphone Types: under-video-monitor conference bar, center–of–table array microphone
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Large Conference Rooms
This style of conference room is becoming increasingly popular. Quite often, this takes the form of two adjacent rooms that can be used in divide/combine mode. These would usually have flexible seating layouts: schoolhouse, donut or U-shaped conference setup, or multiple individual small collaboration tables. (The last can be quite tricky, as you can never be sure where the tables will be for a given event.) It is imperative for your microphones to cover the room evenly, so as not to point at specific locations. Rooms like this most often benefit from very well positioned and adjusted ceiling-tile-style beamforming array microphones. These microphones can take some time to configure, but the results can be amazing.
When using different kinds of microphones, you must be careful to control the overlap between the different devices. For example, if one of your ceiling beams covers the same area that the lectern microphone does, you will create phase-alignment issues that present as a compromised frequency response. This will usually make the lectern position sound “tinny,” with minimal low- and low-mid-frequency energy. This is often caused by the lectern microphone being connected to the DSP as a direct analog device, whereas the ceiling mic is a digital device that processes the signal before sending it to the DSP via a digital connection (like Dante). A short delay inserted in the lectern microphone can often improve this. If, however, you have moving beam-array microphones trying to cover the same area that your lavalier and handheld wireless microphones are covering, the fix can be far more difficult than a short delay. Look up “3-to-1 Rule” for more on this subject. As I said previously, physics still applies, regardless of technological advances.
When I use gooseneck microphones, I like to talk directly into them, hopefully getting a minimum of “plosive sounds” as a result of proximity effect. I also like to test them talking at 90 degrees to the mic. Many presentations are done from lecterns, and this often also involves a video display to accompany the presentation. When describing the video to the audience, the presenter will often look at the screen, projecting their voice across the microphone, as opposed to speaking directly into it. This changes the sound of the voice dramatically. That said, it’s easy to find a couple of short shotgun microphones on the market that solve these issues.
The same issue applies when you’re choosing gooseneck microphones for a boardroom table. Most participants will rarely speak directly into the mic, choosing instead to talk up or down the table to the other people sitting there. Make sure that the goosenecks are long enough to reach over the top of the screen of a standard laptop to avoid the obvious issues. Alternatively, mount them off to one side or the other so they don’t get covered up.
I think we have finally moved beyond table-mounted button mics. It was difficult to stop participants from covering them with folders, computers and other stuff. With this style of mic, rustling paper, banging, taps on the table and other annoying issues were, and still are, difficult to control.
Suggested Microphone Types: ceiling-mounted beamforming microphone arrays, wireless bodypack/lavalier and handheld microphones, lectern gooseneck microphones and wired table-mount gooseneck microphones.
Microphones for Large Boardrooms
Generally, a boardroom would be the top of the line for most companies’ conferencing needs. Normally, this would be a “white glove” room, with the AV team in a control room mixing both the audio and the video. Ceiling-mounted tile-style beamforming array microphones can be acceptable here; however, I’ve often found that the ceiling design doesn’t support the positioning and appearance of these. Also, many designs are looking for the ability to voice lift one area of the room, while growing progressively louder to the other side of the room. This kind of ceiling array of both microphones and speakers takes some careful balancing and equalization. Often, the result can only be heard when you turn the system off and hear the difference when the “lift” goes away — subtle, but effective. There are a few manufacturers that offer small-format ceiling microphones that can be used for this kind of setup.
Wireless microphones are a useful, although also challenging, option. They should therefore only be considered when there is no practical way to use a wired alternative, or if the configuration of the room is always changing. The biggest thing to think about is the small bandwidth of radio frequencies assigned by the FCC for use in our industry. The more frequencies you want to use in a conference center, the higher the resolution those devices need to be, and the more expensive they become. Using RF in an office building out in the middle of the country is difficult enough. Configuring one in a high-rise office building in the middle of Manhattan is a whole other issue!
There are 2.4GHz/5GHz systems that work well for conference centers, although, when you’re in a boardroom, you would be better off considering systems in the 470MHz/530MHz or 925MHz/960MHz range. In some instances, you will need an FCC license for some of these. Since this range includes some local TV channel interference, it depends where you are as to how many channels you would be allowed to use. We have installed complex spaces in Manhattan that have 50 to 60 wireless microphones operating on one floor of a building — but it’s not without its challenges, and it’s not without interference from other companies’ offices above, below and in the surrounding buildings. Be a nice neighbor and use as little transmit power as you need — and only enough antenna to pick up inside your space. Transmitting out to the entire neighborhood, or picking up a spaceship flying overhead, is not required for an office system.
In addition, you must choose a handheld microphone head wisely, as most presenters don’t have the best microphone technique. Often, they tend not to point the microphone at their mouth unless reminded to do so. It doesn’t matter how good the microphone is: It will not work if it’s not in front of the person’s mouth. There are some new microphone heads from a couple of manufacturers that sound excellent for this purpose. I especially like the new dynamic cardioid heads that control proximity effect better than the condenser heads can.
Related: Best Practices For Sanitizing And Cleaning Microphones
Microphones for RF bodypacks are another contested issue. You can choose to use lavalier-style or earset/headset-style microphones, or perhaps a combination of them. I’m still a fan of omnidirectional lavs, as the positioning of cardioid lavs can be difficult. (And, in most instances, they feedback more easily than omnis do.) Earsets are available in both omni and cardioid, as well. Again, here, the omnis work quite well. With this style, you get what you pay for. If you start looking at the best available, you’ll probably find that they work as well for you as they do for Broadway performances.
I have always liked the look and sound of gooseneck microphones on a boardroom table. The technology looks like it means business, and it works better than any alternative I’ve seen. I was upset when my favorite short shotgun gooseneck was discontinued by its manufacturer; happily, however, another company stepped up to the plate. I encourage you to look at the short shotguns available, and I’m sure you will come to the same conclusion that I have. Of course, if the customer or their architect doesn’t like the look, you will have to investigate the alternatives.
Please use a microphone that sits in the table — not one that merely sits on the table. If you don’t make the microphone obvious, you have no chance of stopping the participant from covering it up with their stuff. It is important to remember this truism: If the participant can move them, they will move them. There are other options besides high-quality goosenecks, but, generally, they’re not as good.
Suggested Microphone Types: multiple ceiling-mounted microphones with multiple small speakers in a mix-minus voice-lift array, wireless bodypack/lavalier and handheld microphones, lectern gooseneck microphones, and wired and/or wireless table-mount gooseneck microphones.
Conference Auditoriums
Another trending room type is the 300- to 600-seat auditorium with a large video screen and stage. Sound systems can be behind the screen with surround-sound speakers around and above the audience. Additionally, there is usually a voice-propagation system located to the left and right of the stage. There are also onstage audio monitors for questions to those on stage from the house, as well as from the far end of a call. This is more like a performance stage than a conference room. However, in reality, both functions need to work here.
Having assessed the seating capacity, you will be using a quantity of ceiling-mounted or pole-hanging beamforming arrays evenly spaced over the audience area so both the far end and the stage presenters can hear questions from the audience. Voice lift is somewhat more difficult in this environment. You could use ceiling-mounted Atmos speakers for this, but you would need separate channel drives to each speaker so you could set up the mix-minus array. The other alternative would be to put the left side of the audience into the right voice system and vice versa. This doesn’t produce the best result, although it’s perhaps better than having no voice lift at all. In any event, these microphones would only be turned on during the Q&A. Otherwise, there would be far too much room noise transmitted to the far end.
My previous comments regarding lectern gooseneck and wireless microphones apply here. In all cases, your audio system is only as good as the quality of the microphones connected to it. This is not a place to value-engineer a project.
The so-called “Fireside Chat” format is also popular in these spaces. Often, a presenter will speak from the lectern to present their product, their view of the market, etc. This is followed by a sit-down chat that includes a representative of the company hosting the event. We have done this with RF earsets, lavalier mics, handheld mics and RF gooseneck bases with different-length goosenecks. Here’s the story: If you choose a wireless system for spaces like this, make sure that they’re flexible enough to provide a selection of transmitters and microphones without having to have multiple receiver systems.
Dais setups are best done with wired bases with gooseneck mics, but they can also be done with wireless bases if the budget and frequency space will allow. Here, I would reiterate my previous comments regarding gooseneck mics.
Suggested Microphone Types: multiple ceiling-mounted beamforming microphone arrays, wireless bodypack/lavalier and handheld microphones, lectern gooseneck microphones, wired table-mount gooseneck microphones for dais and “Fireside Chat” formats.
Your Mileage May Vary
The guidelines set forth in this article should help you choose the best microphone type in each of these circumstances. However, as with everything else in AV, your mileage may vary. I can remember a dozen instances off the top of my head when we had to do something different from the above in order to make an installation work. As ever, there is no one-size-fits-all solution.
Once the application becomes more complex than the everyday instance, it is best to bring in a qualified audio design engineer to help you develop the best solution for that particular space.
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Mike Sinclair is president and founder of Sinclair AV, Inc.
