Recording voice at home: where to hang acoustic panels

A voice recording shows up the room mercilessly. Your ears quickly get used to the sound of a space, but a microphone doesn’t – it captures every reflection. That’s why even a good microphone in a bare room produces a recording that sounds hollow and amateurish. Editing can only improve that a little, so it’s far better not to record the reflections in the first place.

Why you can hear the room in a recording

Condenser microphones, the usual choice for voice-overs and vocals, are very sensitive. They pick up not only your voice but also its reflections from the walls, which arrive a moment later. Early reflections, up to about 20 milliseconds, change the tone of your voice – it sounds boxy or nasal. Later ones are heard as reverberation that smears the ends of words.

De-reverb software only helps up to a point. Push it harder and your voice starts to sound metallic and unnatural. That’s why studios sort out the room first and leave editing for small corrections.

How much reverberation you can keep

For recording, you want a short reverberation time – around 0.3 s or less where you record. The room doesn’t need to be completely dead, but your voice should sound close and dry. You can always add space in editing; taking it away is practically impossible.

A panel behind your head

Most voice microphones have a cardioid pattern: they hear best what is in front of them and less of what is behind. In front of the microphone is you – and behind you is a wall. Your voice bounces off it and comes straight back into the most sensitive side of the microphone. That makes the panel behind your head, at mouth height, the most important one in a voice-over corner. If you record sitting down, the centre of the panel should be at about 120 cm; standing, at about 160 cm.

A panel behind the microphone

The second key surface is the wall in front of you, behind the microphone. Your voice hits it hardest. The microphone hears less from behind, but the reflection from that wall comes back to you, bounces off the wall behind you and reaches the microphone a second time. A panel in front of you breaks that path at the very start. It helps if it’s at least as wide as your shoulders.

Side walls and ceiling

Reflections from the side walls reach the microphone at an angle. You can find them with the mirror method described in our guide to panel placement. The ceiling above your set-up reflects sound too, and our panels aren’t designed for ceilings. In a small room, a rug under the set-up and panels arranged so that no large, smooth surface faces another will help.

Why 10 cm for recording

The voice has plenty of energy lower down, especially a low or voice-over voice speaking close to the microphone. A 5 cm panel deals well with mid and high frequencies, but in the lower band, around 125–250 Hz, a 10 cm panel does noticeably more. According to the material manufacturer’s indicative data, at 250 Hz a 10 cm panel absorbs almost all the energy and a 5 cm panel about two thirds. In a recording, that’s the difference between a full voice and one with a boomy bump. There’s more in our guide to 5 or 10 cm.

Voice-over, podcast and vocals

Voice-over usually means one person close to the microphone, recording long stretches of text. A well-prepared corner is enough: panels behind you, in front of you and to the sides.

A podcast often has two or three people, each with their own microphone. Every microphone also picks up the others’ voices reflected off the walls, so the treatment needs to cover more of the room. Hang panels behind each speaker and on the side walls between them.

Vocals are louder and more dynamic than speech, and singers move around at the microphone. You need more absorbing surface, spread more widely, and thicker panels.

What panels won’t fix

Panels won’t silence traffic, the neighbours or your computer fan. If you can hear outside noise in the recording, that’s a soundproofing problem, not an echo problem. Record at quieter times, move the computer away from the microphone, and seal the door and windows. We explain the difference in soundproofing vs acoustic treatment.

Testing the room before you record

Before you hang anything, record a short test. Put the microphone where you usually record and read the same passage in a few places around the room – near a wall, in the middle, a third of the way along. Listen back on headphones. You’ll usually hear straight away where your voice sounds boxiest and where it sounds cleanest. That tells you where to set up and which walls to treat first.

Repeat the test once the panels are up. Pay particular attention to the ends of sentences and short pauses: in a well-treated room, the silence after a word really is silent, with no wash of reflections.

Booth, screen or panels

A reflection filter – the curved shield that mounts behind the microphone – mainly helps with reflections from the wall in front of you. It doesn’t stop sound bouncing off the wall behind you, which lands on the most sensitive side of the microphone. So a filter without panels behind your head usually helps less than people expect.

A vocal booth isolates you from noise and is lined with absorbing material, but it takes up a lot of space and costs many times more than a few panels. Unless you record somewhere noisy, a well-treated corner of an ordinary room sounds very similar, and the room can still be used for other things.

Typical sets

• A voice-over corner at a desk: two 60 × 120 cm panels, 10 cm thick, behind you and one or two in front of you, behind the microphone.
• A podcast room of 10–12 m²: six to eight 10 cm panels – behind each speaker and on the side walls.
• A vocal corner: panels behind, in front of and on both sides of the singer, 4–6 m² of absorbing surface in total.