Home studio aocustics

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Not all studios are created equal.

Anyone can buy some budget monitors and a cheap microphone, stick them in the corner of a room and voila! Home recording studio.

But what separates the wheat from the chaff is the ability to make the right tweaks that will take your recording game to the next level.

Use the following tips to turn your humble home set-up into a well-tuned recording studio.

Accuracy VS Soundproofing.

There are two main factors that you need to control to achieve good acoustics in home studios: accuracy and soundproofing.

Vital to a good mix is the accuracy of sound reaching your ears. The main factors affecting the accuracy of sound in your studio include bass control, reverberation reduction and monitor set-up.

Soundproofing refers to the reduction of the transmission of sound pressure from one room to another. If noise leaks into your room from adjacent spaces, then your mix can become polluted and you will disturb users in other rooms with noise spilling over from your studio.

Sound Accuracy

Trap The Bass.

Small / medium sized rooms are always going to suffer from uneven frequency responses – creating problems with the low-end of mixes.

By trapping bass in your studio, the details, balance and timbre of your mixes will be that much better:

  • To get the most bang for your back – treat the corners of your room (this is where the greatest sound variation will occur).
  • You can buy ‘kits’ of four foam bass traps for your room’s corners from online acoustic and music stores. Be sure to get bass traps that are at least 2500mm deep (10 inches) in order to achieve significant bass control. Popular brands are Owens, Universal Acoustics & Auralex.
  • Most bass traps can simply be glued in the corners of your studio. If you want to do it properly, however, separate the foam from the walls using a mount – leaving a gap to prevent the direct transfer of sound energy to the walls.

Kill The Reflections.

Reducing echo and reverberation is the next step that you need to take.

Don’t know whether you have a problem with echo? Stand in the middle of the room and clap. Can you hear an echo bounce back? Yes? Then continue below…

  • The first reflections you must tackle are primary reflections. These reverberations are produced by the sound energy that strikes the wall after leaving your speakers.
  • If you have your monitors correctly set-up then you can try placing acoustic absorbers made from high-density fiberglass at head height, to the walls to the right and left of your mixing position.
  • Make the absorbers wide enough to cover the space on the wall between you and the monitors. This should control the reflections.
  • Place an additional absorber above your head in the mixing positon. This will tackle reflections caused by a low ceiling.
  • Consider adding additional panels directly behind your speakers to prevent any reflections caused by speaker kick back.
  • Address the rear walls. A common way to do this is to use a combination of acoustic absorbers and diffusors. Diffusion is the breaking up of uniform soundwaves so they become less disruptive to the human ear. It is nigh-on impossible to eliminate all echoes; so diffusion is often a good way to deal with stubborn soundwaves. You can find online tutorials for DIY diffusors; however, a really cheap way to do this is to use a bookcase containing CDs, books and other miscellaneous items of different depths and sizes and place it at against your rear wall. This can help to scatter soundwaves

Quick Tip:

Primary Reflections are also known as mirror points, due to a well-known method to control them. Sitting in your mixing position, have a friend gradually move a mirror along the walls to your sides. Once you have a clear view of your monitor from your position – this is the primary reflection point on your wall. Repeat with opposite wall.

Quick Tip #2:

Don’t bother spending hundreds on designer acoustic panels used in commercial spaces, making your own acoustic panels is quite simple and the internet provides dozens of tutorials. Simply source some fibreglass or Rockwool sheets of at least 50mm (2 inch) thickness. Wrap the sheets in some transparent fabric (if you can feel your breath pass easily through the fabric, it is fine). Attach the fabric using spray adhesive and use simple picture hangers to fix the panels to your wall.

Monitor Set-up & Mixing Position Are Key

Speakers

  • For good stereo imaging, a common practice is to create an equilateral triangle using the two speakers and your mixing position as the points of the triangle. Make sure the speakers are angled in to face you and not facing parallel to your walls. This will help you hear more of a direct sound from the monitors and less of the room’s reflections.
  • Speakers should be facing the right way up and placed on their own decoupled stands and positioned at your head height.
  • If you have to place the speakers on your work station, then use isolation stands to decouple the speakers from the desk and reduce reflections from the work surface.

Avoid Room Modes

  • Each room has its own resonant frequencies or ‘modes’. The key to setting up your workstation, listening position and monitors is to avoid frequency and harmonic ‘nulls’ that exist in halfway points in most rooms. Avoid placing yourself in the centre of the room, specifically avoiding middle points between front and back walls and the floor and the ceiling.
  • A common practice in a standard rectangular room is to place your listening position 38% of the distance of the room away from the front wall. Use this as an indicator and not as gospel – just avoid nodal points such as at 25% or 50% of the room’s length.
  • However, for a balanced stereo image, position yourself centred between the side walls.
  • To prevent additional side wall reflections, place your speakers along the longest walls in a rectangular room.
  • Try to avoid putting the monitor too far in to the corners of the room. Kickback from the speakers can reflect off walls behind the speakers. Increasing the distance between the speakers and the walls they are facing away from is a good practice. So is adding absorption to these walls.
  • Use a program like Room E1 Wizard to measure your room’s frequency and highlight trouble spots to avoid.

Soundproofing

Soundproofing your room is no easy task and can quickly become expensive.

Most DIY studios won’t have the budget to build a proper soundproofed room, but you can still make significant improvements at low cost.

Unfortunately to achieve significant soundproofing in your standard room you need to have the scope to undertake some type of construction. If you have the opportunity – removing existing plasterboard, adding insulation, decoupling frameworks from the plasterboard and then building a secondary wall on-top of this improved wall will give you a good level of soundproofing in your room.

Mass – The First Line Of Defence

Wall density is the single most important factor to sound attenuation. For every doubling of mass added to a wall, you will roughly half the amount of noise transmitted through the wall.

For most home studios, existing walls will be made of a lightweight, cheap building material that will leak plenty of noise.

  • If you have the skills to build an additional wall, then add mass by lining existing walls with studding and plasterboard and then filling the void with insulation.
  • Adding two or more layers of plasterboard is best to build a decent amount of mass.

Decouple, Decouple, Decouple

While adding mass alone is a good starting point, the new frames should be separated from the existing walls to create an air gap – this is known as decoupling.

Decoupling is essential as sound is more than happy to vibrate and transfer through physical connections.

  • Neoprone spacers are an easy way to decouple when building double walls.
  • Resilient sound isolation clips such as Genie clips are also a popular product to help with decoupling. These clips hold plasterboards in place to framework while limiting the physical connections between the two. They have an added advantage of containing furring strips inside – z shaped channels that sound must work its way through before reaching studwork – reducing sound energy.

Quick Tip: If you don’t have the scope to build an additional wall, then altering existing walls can help with sound isolation: Replace your standard insulation with high performance sound insulation such as Roxul. Replace standard plasterboard with QuietRock. Lastly, swap your wooden studs with steel studs, which provide better sound isolation.

Seal The Gaps

A soundproofed room is an airtight one. The two main problem areas you will encounter in your studio are doors and windows.

Doors

Your standard door will provide around 15dB of insulation – nowhere near enough for a studio.

  • Replace your standard door with a solid timber door. Glue an extra ¾” piece of plywood to the door to add extra mass.
  • A solid door is useless if it has gaps around its frame. Buy an inexpensive door seal to help with sound leakage.
  • If you have a decent budget – invest in a compression latch that will squeeze the door shut tight against the frame.

Windows

If you are lucky enough to have double glazing – then this can go a long way towards preventing sound leakage from windows.

For those who don’t:

  • Check the existing window for any air gaps. Cover them with expanding sealer foam.
  • Buy a cheap secondary glazing kit. These kits will provide you with an air-tight secondary noise barrier that can help soundproof windows. Make sure the gap between the original glass and the secondary pane is significant. For 6mm thick glass, each 25 mm increase in the gap will reduce noise transmission by 1.25 dB.
  • A cheaper solution can be made using sound absorbing foam and a heavy noise blocking layer purchased from your local hardware shop. A combination of these materials ‘plugged’ into the window frame can be quite effective. Use this diagram as a guide (http://www.customaudiodesigns.co.uk/how-to-soundproof-windows.htm)

Quick tip: Don’t be a sucker for blinds and acoustic curtains. These fabrics are always going to be more transparent than simple, thick foam, and will achieve nothing for soundproofing the studio.

References:

  • Frigoletto, Jay. ‘4 Tips To Improve Home Studio Acoustics | Performer Mag’. Performermag.com. N.p., 2015.  http://performermag.com/4-tips-to-improve-your-home-studio-acoustics/
  • Soundonsound.com,. ‘The Studio SOS Guide To Monitoring & Acoustic Treatment’. N.p., 2015. . https://www.soundonsound.com/sos/feb06/articles/studiosos.htm
  • The Recording Revolution,. ‘How To Create Your Own Mixing Sweet Spot’. N.p., 2014. http://therecordingrevolution.com/2014/03/05/how-to-create-your-own-mixing-sweet-spot/
  • Benediktsson, Björgvin. ‘4 Foolproof Ways To Make Your Home Studio Sound Better – Tuts+ Music & Audio Tutorial’. Music & Audio Tuts+. N.p., 2011.  http://music.tutsplus.com/tutorials/4-foolproof-ways-to-make-your-home-studio-sound-better–audio-9407
  • Arqen.com,. ‘Bass Traps 101 – Your Ultimate Guide To Bass Trap Placement’. N.p., 2015. http://arqen.com/bass-traps-101/placement-guide/