Fig. 1: Most conference room complaints are a reverberation problem, not a microphone problem.
The quick answer
Conference rooms echo because they are boxes of hard, parallel surfaces with almost nothing absorptive in them. Treat the ceiling and the wall behind the screen first, add absorption to one side wall to break the parallel path, and put something soft on the floor. Around 30 to 40 per cent coverage is enough. Poor call audio is almost always the room, not the equipment.
Everyone has been on the call where the person at the far end of the table sounds like they are speaking from a bathroom. That is reverberation: speech reflecting off glass, plasterboard and a hard table, then arriving at the microphone a fraction of a second after the direct sound. The microphone picks up both and cannot tell them apart.
01 /Reverberation, echo and why it matters
Reverberation is the sound of many reflections overlapping and decaying together. Echo is a single reflection arriving late enough to be heard as a separate repeat. In a conference room you will nearly always be dealing with the first, because the room is too small for a true echo. What you hear as an echo is a long reverberation tail.
The problem is not volume, it is overlap. When one syllable is still decaying while the next arrives, consonants blur and speech becomes hard to follow, particularly for anyone on the far end of a call who has already lost some clarity to compression.
02 /Find the reflective surfaces
Stand in the middle of the empty room and clap once, sharply. A crisp clap that stops immediately means the room is fine. A ringing tail or a fluttering, metallic repeat means you have work to do. Flutter usually indicates two parallel hard surfaces, most often opposing glass and plasterboard walls.
| Surface | Why it reflects | Priority |
|---|---|---|
| Ceiling | Largest uninterrupted hard area in the room | Treat first |
| Wall behind the screen | Everyone faces it, so it returns speech to the table | Treat second |
| One side wall | Breaks the parallel path causing flutter | Treat one, not both |
| Glazing | Highly reflective and usually cannot be panelled | Acoustic curtains or screens |
| Hard flooring | Reflects and adds chair scrape | Carpet tiles or a rug |
03 /What to install
- Felt acoustic panels. Made from recycled PET, Class A fire rated to ASTM E84, tested to ASTM C423 and ISO 354. They come in a full colour range and mount with adhesive, so they suit an occupied office.
- Ceiling baffles or clouds. Where the ceiling is exposed or has services running through it, suspended elements bring absorption closer to the table than a flat ceiling treatment would.
- Acoustic carpet tiles. Address the floor and chair scrape at the same time.
- Screens or curtains for glazing. Glass walls cannot take panels, so acoustic curtains or felt screens are the practical route.
04 /Treatment is not soundproofing
Absorption fixes how the room sounds to the people and microphones inside it. It does not stop a confidential conversation being heard in the corridor. If privacy is the concern, that needs mass in the walls and a sealed door, which is a separate project with a separate budget. Panels on the wall will not deliver it, however many you fit.
Related reading: why acoustics matter in workspaces, and office soundproofing for Indian workplaces.
05 /Frequently asked questions
Why does my conference room echo?
Because it is a small box of hard parallel surfaces with nothing absorptive in it. Speech reflects off glass, plasterboard and the table, then arrives at the microphone slightly after the direct sound. What you hear as echo is usually a long reverberation tail rather than a true separate repeat.
Where should the first panels go?
The ceiling first, because it is the largest uninterrupted hard surface, then the wall behind the screen, since everyone faces it and it returns speech to the table. Treat one side wall rather than both, which is enough to break the parallel path causing flutter.
How much of the room needs covering?
Around 30 to 40 per cent of surface area handles most conference rooms. Fully treating a room makes it feel oppressive to sit in, and the improvement in speech clarity plateaus well before that point.
Will acoustic panels stop people overhearing our meetings?
No. Absorption improves how the room sounds inside it. Confidentiality needs mass in the walls and a properly sealed door, which is soundproofing rather than acoustic treatment. They are separate projects and panels alone will not deliver privacy.
Sonit writes about practical acoustics for Indian homes and workplaces, with a focus on what delivers measurable results at sensible cost.
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