It is a common misconception that acoustic treatment of a room and soundproofing a room are the same. They both concern sound management and control but in vastly separate ways.
The aim of acoustic treatment is to improve the quality of the sound in a room (recording studios, cinemas, homes) whereas the aim of soundproofing is to prevent sound from entering or leaving a room in a home close to loud noise such as traffic or a venue in a residential area.
Assessing a room for acoustic treatment involves analysing the acoustic properties of the room so that the right acoustic treatment can applied. The most important acoustic properties a room should be analysed for are reflections, reverberation, standing waves and bass frequencies.
What to Consider When Acoustic Treating Your Space
Size and shape of the room
A larger room will typically require more acoustic treatment to account for the longer room reverb and potential for build-up of standing waves. A smaller room will naturally require less treatment but may require certain treatments such as bass traps to be thicker or larger to counteract the proximity effect of the room.
Positioning
As a rule of thumb for a mix or tracking position, working length ways in a room yields the best results. Avoid being too close to corners, walls, and reflective surfaces such as windows or mirrors. Finding the best sounding position in a room with no treatment will in turn help to then get the most out of the acoustic treatment you add.
Type of treatment
Acoustic treatment usually falls into 3 categories – Absorption, Diffusion and Bass trapping. Absorption as the name suggests will absorb sound within the room and reduce reflections (ambience/reverb) with the thickness of the panel determining which frequencies will be absorbed sufficiently (thicker the panel the lower frequency it will absorb). Diffusion often takes the form of a reflective panel in an irregular shape; this is designed to break up and disperse frequencies back into the room to dissipate naturally. Diffusion will help to even out the internal sound whilst still leaving the room ambience intact, often used in conjunction with absorption. Bass Traps – see point below.
Identifying reflection points
Once the best position has been established the next step is identifying reflection points. Early reflection points will be the surfaces closest to your mix/tracking position (typically to your immediate left/right, above and behind speakers for a mix position). Adding absorption treatment here will immediately focus the sound and improve stereo image as you are now hearing your speakers direct without reflections. Late reflection points are usually found further down the room and are made up of mid/lower frequencies, lower frequencies take longer to form and are slower to travel than higher frequencies, meaning they will form and hit a reflective surface further down the room. You can either add absorption or diffusion (or a mix of both) here depending on how much ambience you wish to keep in the room.
Bass Traps
Typically bass trapping is utilised in the corners of a room as corners can be hot spots for frequencies to collect and multiply. This collection of frequencies can turn into a resonance or room mode, usually in the form of a bass frequency being amplified, and by utilising thick absorption treatment to absorb these frequencies before they can collect in a corner will prevent excessive bass build up.
Monitor Stands/Isolation pads
Studio monitors can cause reflections when the soundwaves hit the desk resulting in an inaccurate representation of the sound coming from your monitor mix. Monitor stands or Isolation Pads can reduce the vibrations that cause this and the low-end build-up in the room.
Soundproofing
On the other hand, Soundproofing uses different techniques to keep sound in a room and not let that sound out of a room. These are adding mass, dampening, decoupling, and sealing gaps.
Dampening and Adding mass usually to your walls makes them heavy enough not vibrate and therefore stop sound from travelling through them.
Decoupling involves creating a room within a room by creating a gap between two layers of drywall the outer layer stops the sound from leaving the inner layer and can be combined with insulation to stop even more sound leaving the room.
Sealing gaps as the name suggests involves sealing any air gaps or seams in which sound leaves from, acoustical sound chalk and weather stripping are often used for this technique.
Esmono Sound Isolation Booths offer this room within a room design providing sound isolation from 50mm (for vocals) to 100mm (for drums) for enhanced recording quality, also customisable with windows and fans. The all-metal Esmono Booths are specialised soundproof chambers made to minimise noise and echoes. They offer flexibility with a variety of uses from recording studios, practice rooms, privacy rooms, voice-over rooms, and much more.
Fibreglass Vs Foam
The difference between fibreglass and foam is both performance and aesthetic. Fibreglass has a higher density (almost 4x) than foam and can therefore absorb more of those nuisance qualities in your mix or recording. It can absorb more of the higher frequencies and continues to work with lower frequencies. This is why foam is often used to diffuse rather than absorb.
The installation of fibreglass is often easier as they come as panels that hook on to Impaler clips increasing the likelihood of them being used again. Foam is often stuck on to a surface with an adhesive meaning they cannot be moved once in place.
The cost to produce fibreglass is far cheaper than that of foam as foam is an oil-based material and oil has risen dramatically in recent years. Foam also degrades over time, so you are more likely to need buy more of it. Whereas fibreglass tends to keep its shape and appearance for much longer.
Ultimately, there should not be confusion between Acoustic Treatment and Soundproofing as they aim to do completely different things, one aims to treat sound in a room, and one aims to stop sound leaving a room. Once you know what you want to do with your room acoustically, that is when you need to think about whether Acoustic Treatment or Soundproofing is the right application for your room.
If you want to know more about the terms we are using throughout this article, check out our Glossary.
