Five Acoustic Mistakes in Live Studios and How to Avoid Them

The most frequent mistake we see is buying acoustic panels before anyone has listened to the room. A studio gets foam on the walls because it looks the part, and the presenters still sound boxy. Panels absorb only certain frequencies, and the problem in a bare room is often elsewhere: a low rumble from a hard floor, a flutter echo between two parallel walls, or a ringing glass partition behind the desk.

Callum Reid, our acoustics engineer, always starts with measurement. He records how long sound lingers at different frequencies and walks the room with a speaker and a microphone at the real presenter positions. The numbers tell us where the energy builds up. Treatment then goes where it is needed, and the budget is not spent covering surfaces that were never the cause.

• Measure at the positions where presenters and guests actually sit
• Listen on headphones as well as reading the figures
• Keep a record so you can compare after treatment

Thin foam tiles are cheap and quick to fit, which is why they turn up in so many small studios. They do take the edge off high-pitched reflections, but they do almost nothing for the low, muddy sound that makes a male voice boom or a desk seem to hum. Presenters sound clearer in the high end and worse in the low end, and the room feels dead without actually being clean.

Low frequencies need depth. That usually means thicker mineral-wool panels set away from the wall, or bass traps placed in corners where low energy collects. These cost more and take more space, so we discuss early where they can sit without crowding cameras or set pieces. A balanced room treats all the frequencies a voice uses, not only the easy ones.

• Corners are the first place to look for low-end build-up
• Thicker absorbers set off the wall work better than thin tiles
• Check that treatment does not block camera or light positions

Treatment inside the room cannot fix noise that arrives from outside it. Air handling, a lift shaft, a corridor with heavy doors, or traffic on a nearby road will all find their way into a sensitive microphone. We have visited studios where the panels were well chosen, yet a steady hum from ventilation sat under every programme because nobody had traced where it came from.

Walk the building with a microphone before any work begins and note what you hear when the studio is meant to be silent. Quiet air handling, door seals and a closed gap under a door are often cheaper than another wall of panels. Where the noise is structural, we say so plainly and tell the client what can be reduced and what cannot, rather than promising a silent room.

• Record a minute of room tone with everything switched on
• Check door seals, ducting and anything that vibrates
• Note noise from neighbouring rooms at different times of day

It is possible to treat a studio too much. When every surface is soft, voices lose their natural warmth and presenters begin to feel they are talking into a cupboard. They tend to push their voices to compensate, which tires them over a long programme and sounds strained on air. Guests in an interview chair, who are not used to the setting, suffer most.

The aim is control, not silence. A little natural reflection keeps speech lively and helps people hear themselves. We usually treat in stages, listening after each stage, and stop when the decay of sound is short and even. Hannah schedules a trial with a real presenter reading a live script, because a person's ear on a familiar voice tells us things the instruments do not.

• Treat in stages and listen after each one
• Test with the people who will actually be on air
• Stop when speech is clear, not when the room is silent

Acoustics are often planned on an empty room, and then a desk, a large screen, a glass backdrop and a row of lights are added. Each of these reflects or absorbs sound. A hard desk surface near a presenter's microphone, or a monitor angled to bounce speech back, can undo careful work done earlier in the project.

We ask for the set design and lighting plan at the start, so that treatment, camera positions and rigging are decided together. A panel can sometimes be built into a set flat or hung on the grid out of shot. Where a client changes the set later, we advise a quick re-check of the room, because a small change in layout can bring back a reflection that had been solved.

• Share set drawings before treatment is specified
• Soften hard desk tops close to microphones
• Re-check the room after any major set change

A studio that sounds right in the week it is finished may behave differently months later. Panels get moved to make room for equipment, a curtain is taken down, or a new piece of kit adds fan noise to the gallery. Without a routine listening check, small changes pile up until presenters notice that something has gone wrong, and nobody can say when it started.

We suggest a short, repeatable test: the same read-through, from the same positions, recorded with the same microphone. Keep the recording and compare it with the first one whenever something feels different. If your crew is trained to run it, you catch drift early, and a quick adjustment is usually all that is needed. Our training sessions cover this check for in-house teams.

• Record the same short script from fixed positions
• Keep each recording with its date for comparison
• Tell the whole crew which panels must stay where they are