Reader Question: Small Meeting Room Acoustics

small meeting room with glass walls

A reader posed a question the other day. He asks;

I have a question for a friend. He has a smallish meeting room capable of accommodating 8 people. The problem is that some of the walls are made of glass.

When doing conference calls, the echo from his room is impossible to handle which leads to a crappy experience for others.

Which room microphone/speaker should he purchase? Ideally, it needs to be able to connect to a laptop that is brought into the room for meetings.

This is sort of question that I enjoy, so I thought it worth sharing my response.

The problem described stems from poor acoustics, very likely arising from a failure to consider the function of the room in its design. Glass walls may make a nice open space visually, but the hard, reflective surfaces can create terrible acoustics. It’s a recipe for echo. A disaster for intelligibility.


In such situations the best remedy comes from addressing the acoustic defects in the room. If possible, work some acoustically absorptive elements into the room. Consider installing some substantial drapery, hanging a tapestry, or adding upholstered furniture. These things can absorb some of the energy that would otherwise bounce around the room, diminishing resonances, reducing the echo.

Some time ago I wrote about the interesting and inexpensive MIO Paperforms 3D paper tiles that purport to be a real acoustic treatment. I still think that these are very interesting. They can be worked into the design of the space, improving both the appearance and acoustics. MIO paper forms are offered as diffusive elements. They don’t reduce the amount of energy in the room, but they break up specular reflections, making them less damaging to conversation.

The powers that be may not grant you the latitude to alter the surfaces of the room. This ties your hands. It forces you to consider lesser solutions. Solving the problem at its source is always the most effective strategy. Anything else will not be as effective.

If the space in question is an office for just one person I’d suggest that person simply make use of a good headset. A headset largely takes the room out of the situation. A headset microphone is so well placed that the room has little opportunity to be heard.

Polycom SoundStation IP7000 600px

However, the email described a meeting space, which suggests a conference phone is required. Though an older design, the Polycom SoundStation IP7000 remains my reference for such things. It’s a brilliantly effective device. In this case it’s perhaps a bit too large for the space. Further, it’s fundamentally a SIP phone, although it does have a 3.5mm TRS jack that allows analog connection to a computer.

Polycom’s SoundStation Duo is about the right size. Like the IP7000, it has an analog jack for use with a computer. The troubling part about the SoundStation Duo is it’s hefty umbilical cord, which in this instance would be providing only power. That such cabling would be visible seems antithetical to a space with glass walls.

In my mind, the lack of USB connectivity takes the two Polycom devices out of consideration.

The simplest choice would be a ClearOne Chat 160 Group Speakerphone, like the one I reviewed in 2011. These are relatively affordable and perform well. They’re only USB devices, meaning that they require a computer to be functional.

Konftel 300 IP Conference Phone

If a more flexible device seems appropriate, I’d look at the Konftel 300 Series. There are several models with different connect methods, including; analog phone line, SIP over IP, Bluetooth, and USB. There’s even a battery-powered, DECT wireless model, the 300wx.

“…it’s in the way that you use it.” – Eric Clapton

How you deploy the conference phone, specifically where it’s placed in the room, can improve your results. Most meeting rooms are either rectangular, or worse, square. In the very middle of a table, in the middle of a square room, is typically the most resonant location possible for a conference phone. It’s the one place where the poor acoustics of the room pile up, presenting the worst source sound for the conference phone.

Fortunately, it’s not that difficult to improve upon that poorest of device locations. Shift the conference table to be slightly off-center in the room. Shift the conference phone to be off-center of the table. All it takes is 18” change in position to markedly improve the sound at the conference phone. A little experimentation with device placement is worth the effort.

A poorly considered meeting room may not be a problem for the people actually in the room. It’s the others on the call, those at the far end, that suffer the worst of problem. As in most things, knowing that there’s a problem is the first step in finding a solution. Whatever you elect to do, be sure to check with the distant meeting participants to see if their experience is improved. That should be the measure of success or failure of the remedial strategy.

I’d be interested to hear any similar experiences that you could share. How did you treat a poor meeting room? What conference phone was most satisfactory?