Is sound treatment the same as soundproofing?
Welcome to the first edition of Studio Dynamics, a monthly column created to help you understand what's going on in your studio. Whether or not you have a pro studio, home studio or just a workspace in your home or office, it is important to have the space setup correctly, to help achieve the best results and make it comfortable to work in. Each month I will cover a topic that will help you to understand your working environment and create improvements that will make you more efficient, get better sounding results, and help you gain a complete understanding of your equipment and what you have to work with.
As this is the first edition, I put a lot of thought into what to talk about and how to introduce the column to the world. Before we get into equipment, techniques or anything else, I think it's very important to talk about the room you are working in. Starting at the beginning with a good sounding space is the best way to get the results from your equipment that you are looking for. And let's face it, you invest a lot into your equipment, so you should invest the time into making sure you are hearing the sound as accurately as possible in your room, and that you are maximizing the potential of your space.
So let's talk about your space. It doesn't matter if it is a full on professionally designed studio, or just a bedroom in your house, with the right kind of sound control treatments, any space can be made to sound better. Now I'm not going to lie, I didn't say "can be made to sound great", I said "made better". To get very accurate mixes and to hear things properly, you really do need a well-made room designed by an experienced audio professional. If you have a budget to hire someone to help you, that's great, but there are many things you can do yourself to see substantial improvements in your own space.
I mentioned sound treatment above. That is a phrase that is used a lot to describe many things, and is often used in conjunction with the term "soundproofing." People tend to use them interchangeably, but are they the same? Is treatment (or sound control) the same as soundproofing? Well, as it turns out, a lot of people do interchange those phrases, and do use them incorrectly on their own. I'm starting here because I want you to make sure you know the difference between the two before we move forward. If we are to maximize your working space, we have to fully understand what is, and what shouldn't be expected from your room.
Let's look at why they are different. One official definition of soundproof or soundproofing is to make a room or building resistant to the passage of sound. Well, it's not really sound, but the sound pressure level, and reducing that pressure between the source that is generating the actual sound pressure and you. Let's say for example you have a band and you like to record in your house at night after everyone is off work. Your neighbor is in the house next to the room you practice in. Following the definition of soundproofing, you want to reduce the sound pressure levels between your band and the neighbor. If the band kicks into their famous cover of "Smoke on the Water" it generates pressure waves at certain frequencies and those waves travel to your neighbor's house, they will be heard and possibly felt depending on the frequencies generated by the band. Soundproofing may also be trying to create separation between a control room and the tracking room in a recording studio. Or it may be trying to contain the sound in one room so it doesn't bother people in an adjoining room, like in an office or if you work at home and other family members are there. Basically, any time you are trying to stop or greatly reduce sound volume (or sound pressure level) between two spaces, it is considered soundproofing.
There are a few ways we can approach reducing the sound pressure created by your band. First, we can increase the distance between the receiving end (the neighbor's house) and the source of the pressure wave (the band). But this is probably not the best solution since neither of you want to move. If increasing the distance between the source and destination is not feasible inside your studio, house or room, we could use noise barriers to disrupt the signal path between the destination and the source. Noise barriers reflect or absorb sound, reducing this unwanted sound pressure. We could add barrier technology to our practice room walls and ceiling, which is between us and the neighbor's house. This would create a sound pressure barrier that would disrupt and break down the sound pressure level between playing "Smoke on the Water" for the 12th time, and the neighbor.
Electronic noise cancellation technologies can also act as soundproofing, attacking the source itself. Using a sophisticated electronic signal generator, one can cancel certain unwanted sound pressures electronically by introducing an inverted waveform (a wave 180 degrees out of phase from the source) of the noise and thus producing noise cancellation. Noise cancellation headphones are an example of this electronic sound pressure reducing technology. This technique is also used in public areas and commercial facilities. You don't find this technology too much in the studio other than very special situations too complicated to get into here.
Soundproofing is all about reducing sound pressure from the source to the receiver. In a ground-up build, or a major renovation of a studio or workspace, this is not a super hard thing to achieve. Sound proofing elements are easily purchased, and as long as they are installed properly, can have great results. The problem with soundproofing is, to achieve good results, it usually takes a lot of material expense, and some type of construction and acoustic know-how to get the required results. You can't just put acoustic foam up in the practice room walls and expect the neighbor not to hear the sound anymore. This soundproofing issue would require that we use barrier technology.
To stop the sound pressure requires looking at many things. You have to remember that sound is like water, it will always find a way through. If you patch just one spot on a roof with many holes, the water (or sound) will just move sideways until it finds a new path to get in. To achieve adequate sound proofing results, you need to consider that sound travels through physical openings in the walls as well as through vibrations between the source and destination. To stop - or greatly reduce - the sound pressure waves, specialized construction is usually needed. Walls are created much thicker than normal residential or commercial construction calls for to create great mass to stop the sound. Much care is taken to make sure every opening and hole between the walls are sealed beyond what would normally be done. But probably the most important part is the hardest one to deal with. You have to stop the surfaces of the walls, floor and ceiling from vibrating and passing the sound wave through the wall. In regular construction, all of the wall studs, headers, footers, roof rafters, floors and walls are attached together and touching each other. If one starts to vibrate, it travels between everything and can literally pass a sound pressure wave from one room to the next, or even across a whole house, building or over to the neighbor's house. There are many different techniques used to stop that vibration, but they all require some type of construction or rebuilding of the structure. The subject of proper soundproofing is very deep and very well documented all over the web and in books. It is too much to go into specific detail here, but you can easily explore the subject on your own.
Different soundproofing methods are used to deal with different soundproofing problems. We can use noise barriers or other damping technologies depending on the particular soundproofing issues we are faced with. In the end, soundproofing deals with noise from the outside getting to the inside of rooms or the stopping the sound from going from one space to another, but we still get calls all of the time from clients asking us to fix their sound issues, and they do believe that putting up foam or fiberglass panels on the walls will qualify as soundproofing and stop the sound from going between the rooms. They are always disappointed to find out that that is not the case. Sound treatment is much different in that you are now just dealing with controlling the sound within a room to make the space sound better and more accurate. It does not stop sound from going from one room to the next or stop outside noise from entering the room.
For sound control/treatment there are several products to choose from. There are many manufactures like Primacoustic, Aurlex and more that make pre-made cloth covered fiberglass panels and other sound control products. A simple internet search will show you a plethora of choices to buy. But what do you need for your space? Broadband absorbers, diffusers, bass traps and ceiling clouds are some of the choices readily available. If you don't know what any of these terms are, or you aren't sure which ones to choose for yourself or how to place them, check in here next month as we start to explore these solutions and techniques for good sound control habits.