One of the most commonly implemented acoustic treatment materials in home recording studio are the egg cartons. They are very cheap solutions and easy to find. You can find a lot of egg cartons in department store or every time you buy a dozen of eggs in the public market.
Yet the main question remains: “Are they really effective for acoustic home studio treatment?” A quick browse in major recording forums leads to a “NO” answer. Most of them agreed that egg cartons are a waste of time in terms of home studio acoustic treatment. Still they do not provide technical details why it is NOT advisable. I am doing some research fascinated by the egg cartons and investigate why they are not a perfect solution to treat your home recording studio environment.
Sound Absorption Coefficient of Egg Carton
The real answer lies in examining the sound absorption coefficient of egg carton. In most sound engineering literatures, these data is missing. However I did further research and found out a study entitled: “Measurement of the sound-absorption coefficient on egg cartons using the Tone Burst Method” authored by: Quintero Rincon Antonion of Argentina.
The conclusion of the study summarizes the sound absorption coefficient of egg carton in different frequencies, see screenshot below:
Surprisingly egg carton does have significant sound absorption particularly for middle and high frequencies. Starting at 1000Hz to 4000Hz, it does reduce the sound at middle frequencies at an absorption coefficient of 0.69.
Comparing this with the common sound absorption coefficients of rigid fiber glass (the standard acoustic treatment material used in recording studios):
Image credits: ethanwiner.com