1.What are You Working With 2.Where Do I Put My Gear? 3.Carpet, Foam, and other things 4.Material Choices 5.Trapping the Bass 6.Upon Reflection 7.Putting it all Together 8.Summary If you are anything like me, you look at pro music studios with a little bit of envy. Just the vast array of outboard gear is enough to make me salivate. As a hobbyist not working in or owning a studio, I simply do not have the cash to spend on a whole room or outbuilding dedicated to recording and mixing my music or practicing techniques. With their ‘Floating Room’ construction, odd shaped rooms, lack of external facing windows and crazily thick walls, a recording studio is understandably built to be the most neutral listening and recording space possible. Conversely, a home studio is full of the usual home furniture like a sofas, beds, tables and other items that reflect and absorb sound in different ways, and it may not be possible to move these to create a space to start creating your ideal studio room. In this article, while trying to keep the explanations in as plain English as possible. We’ll be looking at what you can do in your home studio to adapt the acoustic properties of your particular space to make it as neutral as possible, for both recording and mixing, and help mix your tracks with the confidence of a full-time producer!
A home studio most typically could be a bedroom, spare room or in my case, a conservatory. This obviously can cause some issues, first of which is your room’s shape. When you are talking about acoustics about room shape, one basic tenant is important to note above anything else, and that is: Symmetry is bad. A room that is symmetrical can create reflections that can seriously distract the listener from what they should be hearing from the monitors in front of them. The idea behind acoustic treatments for a studio is to find and even out the dead and boost spots of all frequencies. For this to be achieved the surfaces in the room, need to be optimized by way of making them asymmetrical using absorption and dispersion techniques, and thereby avoiding reflections reaching your ears. Before we delve into the acoustics side of things, let’s cover a few quick pointers for placement of your gear, as acoustics are but one part of making your setup sound as good as it can.
First of all, the positioning of your equipment is of vital importance, and if you want to start in the right way, the desk you are sitting at should never be at the midpoint in a room either from ceiling to floor or side to side. In a regular room where two walls have the same dimensions, this can create dips and boosts of certain frequencies. Also, once your monitors are placed on the desk, this can cause a varying and uneven bass response. A way around this could be to use monitor stands or risers, that would ensure the height is slightly higher or lower than the midway point. This has an added bonus in that it removes the potential of sound reflection from the desk itself by de coupling them. The speakers should always be at head height where ever possible and never be on their side, as whilst this looks really cool, it can affect the sound dispersion pattern in a way that is not entirely accurate when it reaches your ears. Of course, the exception to this is if you happen to have speakers meant to be on their sides.
Where placement is concerned, speaker angle is also very important. I am sure that those of you who have home cinema setups have found that completely straight speakers just don`t get you the best experience. To make sure that the stereo sound field and therefore your mixes are accurate, monitors should be placed at an equal distance apart to the distance of the listening position and, at angles equaling 180 degrees in relation to your listening position. This means that each monitor will be placed at the 60-degree mark when looking at a protractor. In practical terms, this means that the monitors are directly pointed at your ears, and if you were to look at yourself from above, you would see that your listening position and your monitors would make an equilateral triangle. Once these adjustments have been sorted out, you should already be able to appreciate the differences from the sound you were getting before, but don`t get too excited just yet as there is a little way to go to optimize our space. Next up, The acoustics!
When I was in college, I heard tales of how some people used to ‘sound proof’ their recording space, and what they would use. I thought nothing of it at the time, but now I realize why some of their mixes sounded pretty awful (ignoring their mixing skill of course!) They would use flimsy blankets, and old bits of carpet shoved everywhere in the room, so it looked like a Yurt. They would then record in the fabric bubble, and when they return to the room to listen back, their mixes were so lacking in high end when recording, yet quite treble heavy when listened to anywhere else. Blankets, Carpets and the like, being thin, are terrible at absorbing low end, and anything less than around 400Hz just sails on through, which meant that to compensate for what they were hearing, my colleagues would boost the mids and highs, creating an awful din. I suppose what I am trying to say is, choosing the correct material for the right application is critical in achieving the intended neutral results.
Foam is one of the most likely and popular materials you will come across when researching acoustic treatments for your studio, and with good reason. You`ll see Foam pads in all sorts of shapes and colours, and it is very important that you pay attention to your listening position when choosing the dimensions of the pads. If you move around a lot when mixing, you`ll need a larger pad to make sure that all the possible reflection points are accounted for. There are a couple of important facets of Foam that are to be remembered when deciding on it for your space:
Rockwool is another option and is effective in the same ranges as Foam, so is usually deemed a reasonable alternative, however, unless you hate Foam, Rockwool is a bit of a pain to work with! There are however a few places where Rockwool would be better suited. If you have alcoves or a fireplace in your studio that aren`t used, you could stuff these with Rockwool and then cover with a thin sheet of fabric to help even out the reflections from that part of the room. Another perhaps easier option to consider is what’s already in the room. Regarding absorbing and dispersing the reflections on back walls, if there is already a bookcase with books on it (or if not some Foam would do), then the mass of books does a reasonable job in troublesome spots.
Once you’ve dealt with the mid and high end of your frequency woes, the next mission is bass. Often the trickier problem to pin down, bass management is essential to practice in tandem with your Foam blocks for the other parts of the range. In general, bass management involves dealing with materials with a larger mass than Foam. Unless you’d like several feet thick blocks of Foam in your studio. To be efficient and most practical, the solutions you will place in reflection points around the room can combine both Mid/High and Bass management techniques, and also dispersion blocks, with uneven ridges. Commercial panels are available that integrate hollow wood construction traps filled with a combination of loose Foam or
Rockwool, solid Rockwool panels or vinyl barrier matting that is similar to Dynamat to those familiar with vehicle audio. These can be easily constructed if you are that way inclined, and placed in the corners of a room. Here is an excellent walkthrough of building bass trap panels. The most popular place for bass traps is usually each corner of the room, and sometimes will stretch from floor to ceiling to ensure the mass is enough to completely absorb the low end, but unless you have super low and powerful subs, then I would suggest its overkill, but that is your decision! The barrier vinyl is quite thin but can range between around 10kg-20kg/m so if you are planning to install something like it, best to make sure you have pretty decent walls beforehand, place them on the floor, or stick to smaller panels. These will also be covered in a Foam panel thereby creating an all in one solution.
Reflections are created when sound waves hit a surface that is both solid and nonflexible. The amount of reflection back into the room will vary depending on your rooms construction, and on the absorption properties of those particular materials. Here is a good chart for reference. Obviously, the amount of panels you will want depends on both your personal preference and the room dimensions and characteristics, but there are a few place where it is best to place panels in order to control reflections coming back to the listening position. When sitting in the middle of a room equidistant to the side walls, you should look at placing a panel around ear height and The next spot you should be looking at is directly behind the speakers especially if, like me, your desk is in front of double or triple glazed glass. Glass of this type, typically windows, is an absorber of sound which is what we are looking for, however, due to differing thicknesses and construction methods used in windows, I would definately suggest that acoustic panels should be used on the window sill if directly behind the monitors you are using. Third on our reflections checklist is the back wall. This can be the the most confusing reflection point for your ears, so its important to tackle it. Once the sound waves move past your ears, depending on the volume you are working with, they will carry on their merry way to the back wall and reflect back helping to create a disruptive reverb effect. Once again, an acoustic panel similar to our constructed one with Wood, Vinyl and Foam/Rockwool would do well here, at ear height, one each for the speakers, keeping in mind the equallateral triangle positioning we created in the first part.
With all this in mind, lets have a look at a summary of the ideas we have explored in this article in broken down into the medium of bullet points.
I have tried to keep all the above details as easy to understand as possible as, to be honest, to understand all the technical information you need a degree in maths. It just doesn’t make the information accessible. I do hope you have enjoyed the article, and have taken something of use away from it.