Acoustics
Acoustics isn't about making a room silent — it's about controlling what bounces back
Every hard surface in a room sends sound back at the microphone a fraction of a second after the voice arrives. Treatment decides how much of that returns, and from where. Isolation is a separate job with a separate budget. This is how Meros treats acoustics in studios across Sydney.
01 — The two tools
Absorption vs diffusion
Both manage reflections; they do it in opposite ways. Most rooms need mostly absorption, and a little diffusion in the right place.
Absorption
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What it does: converts sound energy into heat inside a porous material, so the reflection never returns to the room.
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Effect on the room: shorter reverberation time. Used heavily, it makes a room feel dead and close.
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Where it belongs: first reflection points, the wall behind the microphone, and the corners for low frequencies.
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Studio use: the default for podcast, voice and small video rooms — speech clarity comes first.
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Cost profile: cheap per panel, and effective immediately. Bass trapping is the expensive end.
Diffusion
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What it does: scatters a reflection across many directions and arrival times, so it returns as a diffuse wash rather than a distinct echo.
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Effect on the room: keeps the room's energy and sense of space while removing the hard slap of a flat wall.
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Where it belongs: the rear wall, and larger rooms where killing every reflection would sound unnatural.
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Studio use: secondary. Rarely worth the money in a room under about 25 square metres.
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Cost profile: more expensive per unit and easier to get wrong. Skip it before you'd skip absorption.
02 — Placement
Where acoustic treatment actually goes
Panel placement matters more than panel count. Four panels in the right positions beat a dozen spread evenly across the walls.
Start with the first reflection points — the spots on each side wall where sound leaves the source, bounces once, and arrives at the microphone. The mirror trick finds them: sit in the recording position, have someone slide a mirror along the wall, and mark wherever you can see the source in it.
The wall directly behind the microphone matters almost as much, because a cardioid mic's rejection is behind it — anything reflecting off that surface arrives from the least-controlled direction.
Corners take the low frequencies. Bass builds up where two or three surfaces meet, and thin panels do nothing for it; you need depth, which is why corner traps are chunky.
The ceiling above the source is the surface people forget. In a room with a low ceiling it's the closest reflective surface to the subject, and a single cloud above the recording position often does more than another pair of wall panels.
03 — How much
How much treatment does a room actually need?
Enough to bring speech reverberation to roughly 0.3–0.4 seconds. Past that you're spending money to make the room sound like a wardrobe.
A typical small studio needs treatment on something like 15 to 25 per cent of its surface area, concentrated at the points above rather than spread evenly. Rooms with carpet, curtains and soft furniture are already part-treated and need less than a bare-walled one of the same size.
The test is practical rather than numerical: clap once in the middle of the room. If you hear a distinct ring or flutter after the clap, there's work to do. If it stops dead, you've gone too far.
Over-treatment is a real failure mode, and an expensive one. A room with absorption on every surface sounds unnaturally close on a microphone — voices go dull, and the result is harder to fix in post than a slightly live room.
The other half of the answer is what you're recording. Voice is forgiving and needs the least. Music, or anything with a wide dynamic range, needs a more careful balance and is worth measuring rather than guessing.
04 — Learn from others
Common acoustic mistakes
Almost all of these cost money and make the room worse, which is what makes them worth naming.
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Using acoustic foam as the whole solution — it handles high frequencies and does essentially nothing below about 500Hz.
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Treating a room for echo when the actual problem is noise getting in, which is an isolation job and a structurally different budget.
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Spreading panels evenly across the walls for visual symmetry instead of concentrating them at the reflection points.
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Ignoring the corners, then wondering why the low end still sounds boomy after a dozen wall panels.
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Over-treating a small room until it sounds lifeless, then adding artificial reverb in post to recover what was removed.
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Leaving the ceiling untouched in a room with a low ceiling — usually the closest reflective surface to the subject.
Studio acoustics FAQs
How much acoustic treatment does a small room need?
Usually treatment on around 15 to 25 per cent of the surface area, concentrated at the first reflection points, the wall behind the microphone, the corners and the ceiling above the recording position. The aim is a speech reverberation time of about 0.3–0.4 seconds, not a completely dead room.
What's the difference between acoustic foam and proper absorption panels?
Thin acoustic foam only absorbs high frequencies and does almost nothing below about 500Hz, so rooms treated with foam alone still sound boomy. Proper absorption panels and corner bass traps have the depth and density to control low and mid frequencies, which is where most room problems sit.
Can you fix a bad-sounding room without rebuilding it?
Usually, yes — if the problem is echo rather than noise. Echo is fixed with treatment: well-placed absorption panels, corner traps and a ceiling cloud. If outside noise is getting in, that's an isolation problem, which means structural work and a different budget.
What's the difference between soundproofing and acoustic treatment?
Acoustic treatment controls how sound behaves inside a room — reducing echo and reflections. Soundproofing, or isolation, stops sound getting in or out, and requires structural work such as floating floors, sealed doors and room-within-a-room construction. Most studios need treatment; only some need isolation.