primary goals of acoustic treatment:
1) To prevent standing waves and acoustic interference from affecting the frequency response of recording studios and listening rooms;
2) to reduce modal ringing in small rooms and lower the reverb time in larger studios, churches, and auditoriums;
3) to absorb or diffuse sound in the room to avoid ringing and flutter echoes, and improve stereo imaging; and
4) to keep sound from leaking into or out of a room. That is, to prevent your music from disturbing the neighbors, and to keep the sound of passing trucks from getting into your microphones.
Please understand that acoustic treatment as described here is designed to control the sound quality within a room. It is not intended to prevent sound propagation between rooms. Sound transmission and leakage are reduced via construction - using thick massive walls, and isolating the building structures - generally by floating the walls and floors, and hanging the ceilings with shock mounts. Sound isolation issues are beyond the scope of this article.
Proper acoustic treatment can transform a muddy sounding room, having poor midrange definition and erratic bass response, into one that sounds clear and tight, and is a pleasure to work and listen in. Without effective acoustic treatment, it is difficult to hear what you’re doing, making you work much harder to create a good mix. In a home theater, poor acoustics can make the sound less clear, harder to localize, and with an uneven frequency response. Even if you spent many thousands of dollars on the most accurate loudspeakers and other equipment available, the frequency response you actually realize in an untreated room is likely to vary by 30 dB or even more. Top
There are two basic types of acoustic treatment - absorbers and diffusors. There are also two types of absorbers. One type controls midrange and high frequency reflections; the other, a bass trap, is mainly for low frequencies. All three types of treatment are usually required before a room mixing decisions and for serious listening.
Many studio owners and audiophiles install acoustic foam all over their walls, mistakenly believing that is sufficient. After all, if you clap your hands in a room treated with foam (or fiberglass, blankets, or egg crates), you won’t hear any reverb or echoes. But thin treatments do nothing to control low frequency reverb or reflections, and hand claps won’t reveal that. Basement studios and living rooms having walls made of brick or concrete are especially prone to this problem - the more rigid the walls, the more reflective they are at low frequencies. Indeed, simply building a new sheet rock wall a few inches inside an outer cement wall helps to reduce reflections at the lowest frequencies because a sheet rock wall that flexes also absorbs a little.
You may ask why you need acoustic treatment at all, since few people listening to your music will be in a room that is acoustically treated. The reason is simple: All rooms sound differently, both in their amount of liveness and their frequency response. If you create a mix that sounds good in your room, which has its own particular frequency response, it is likely to sound very different in other rooms. For example, if your room has a severe lack of deep bass, your mixes will probably contain too much bass as you incorrectly compensate based on what you are hearing. And if someone else plays your music in a room that has too much deep bass, the error will be exaggerated, and they will hear way too much deep bass. Therefore, the only practical solution is to make your room as accurate as possible so any variation others experience is due solely to the response of their room
primary goals of acoustic treatment:
1) To prevent standing waves and acoustic interference from affecting the frequency response of recording studios and listening rooms;
2) to reduce modal ringing in small rooms and lower the reverb time in larger studios, churches, and auditoriums;
3) to absorb or diffuse sound in the room to avoid ringing and flutter echoes, and improve stereo imaging; and
4) to keep sound from leaking into or out of a room. That is, to prevent your music from disturbing the neighbors, and to keep the sound of passing trucks from getting into your microphones.
Please understand that acoustic treatment as described here is designed to control the sound quality within a room. It is not intended to prevent sound propagation between rooms. Sound transmission and leakage are reduced via construction - using thick massive walls, and isolating the building structures - generally by floating the walls and floors, and hanging the ceilings with shock mounts. Sound isolation issues are beyond the scope of this article.
Proper acoustic treatment can transform a muddy sounding room, having poor midrange definition and erratic bass response, into one that sounds clear and tight, and is a pleasure to work and listen in. Without effective acoustic treatment, it is difficult to hear what you’re doing, making you work much harder to create a good mix. In a home theater, poor acoustics can make the sound less clear, harder to localize, and with an uneven frequency response. Even if you spent many thousands of dollars on the most accurate loudspeakers and other equipment available, the frequency response you actually realize in an untreated room is likely to vary by 30 dB or even more. Top
There are two basic types of acoustic treatment - absorbers and diffusors. There are also two types of absorbers. One type controls midrange and high frequency reflections; the other, a bass trap, is mainly for low frequencies. All three types of treatment are usually required before a room mixing decisions and for serious listening.
Many studio owners and audiophiles install acoustic foam all over their walls, mistakenly believing that is sufficient. After all, if you clap your hands in a room treated with foam (or fiberglass, blankets, or egg crates), you won’t hear any reverb or echoes. But thin treatments do nothing to control low frequency reverb or reflections, and hand claps won’t reveal that. Basement studios and living rooms having walls made of brick or concrete are especially prone to this problem - the more rigid the walls, the more reflective they are at low frequencies. Indeed, simply building a new sheet rock wall a few inches inside an outer cement wall helps to reduce reflections at the lowest frequencies because a sheet rock wall that flexes also absorbs a little.
You may ask why you need acoustic treatment at all, since few people listening to your music will be in a room that is acoustically treated. The reason is simple: All rooms sound differently, both in their amount of liveness and their frequency response. If you create a mix that sounds good in your room, which has its own particular frequency response, it is likely to sound very different in other rooms. For example, if your room has a severe lack of deep bass, your mixes will probably contain too much bass as you incorrectly compensate based on what you are hearing. And if someone else plays your music in a room that has too much deep bass, the error will be exaggerated, and they will hear way too much deep bass. Therefore, the only practical solution is to make your room as accurate as possible so any variation others experience is due solely to the response of their room