Why Egg Cartons Are Not Enough To Sound Test Your Studio
If you’ve been in a small rehearsal studio or a friend’s rehearsal basement, you’ve probably noticed that part of the room (probably the ceiling) is covered in egg cartons. Not sure whether or not he’s entered a practice space or shady egg-packing operation, he asks the owner what it is, and he says that egg cartons serve as soundproofing by absorbing sound due to their unique way. Somehow you find it hard to believe him when you walk out of the studio after practice with a really bad case of tinnitus.
Egg cartons for soundproofing are perhaps one of the most popular myths about acoustics. Whether or not this belief was founded by experts or DIY enthusiasts, let me bust this myth by telling you that egg cartons do absolutely nothing for soundproofing. This should be obvious to you when you have a friend yelling right into your ear with just a tray of eggs between the two of you.
In the realm of acoustics, there are different sound frequencies that interact in various ways with their surrounding environment. High-frequency sound waves, such as the sound of a high-pitched squeal or the irritating Epson LX-300 dot-matrix printer, are easily absorbed by layers of porous material such as cloth, fiberglass, and carpeting.
Low frequency sounds like those heard in hip-hop/dance clubs, bass and kick drums are not absorbed as easily (an explanation why you only hear bass when you are near a club or a car with subwoofers drives by with the windows rolled up).
These types of frequencies can be absorbed by structures that have a higher density and mass, such as concrete walls and layers of increasingly thick fiberglass. While an egg carton can absorb some high frequencies, it won’t stop low frequencies from passing through it and is therefore a poor choice for soundproofing. However, egg cartons can be used for sound treatment, such as a poor man’s broadcast.
By its very definition, soundproofing is the inhibition of sound from escaping from a given space in which it is allowed to propagate. If even the slightest measure of sound is heard outside of a “sound proof” area, that area is no longer considered sound proof.
Sound treatment, on the other hand, is the manipulation of a room’s response to frequencies to create a favorable and sonically balanced listening/performance area. Sound treatment can be achieved through absorption, reflection and diffusion (egg cartons can fall into this category).
If you’re helping someone set up a rehearsal studio or making one in your own home, skip the egg carton myth and find more effective ways to treat your space. Creating a soundproof room may be beyond the ability of a hobbyist to budget for (essentially creating a room within a room), but acoustical sound treatment can be had at a reasonable cost.
You have the option of buying ready-made absorbers and diffusers online or at specialist acoustic stores, or you can simply make your own by following the many plans available online – all you need is a printer, a little handiwork and some travel. to the nearest Home Depot.