14 Sep Acoustic Room Tuning 101
After over 40 years in the high-end audio industry, I have learned much about proper set up, installation, and calibration of both 2-channel music systems and surround sound systems. The practical experience I have gained by becoming an authorized dealer for the top audio brands of equipment, and then installing the equipment in my clients homes is invaluable.
The number one factor in creating impressive, immersive, and realistic musical performances in your home, is your home. That’s right. More specifically the room or rooms that you will listen to music and or watch movies in. The characteristics of the room influence the performance level significantly more than any of the electronic components, including the speakers. In order to keep this article concise and enjoyable, I will focus only on the basic ways of room tuning for better sound.
Two channel or stereo systems:
Try to select a room that is rectangular, not square and featuring doors that can be closed to seal the room off from adjacent rooms is preferable to wide open doorways that lead to other rooms.
Set up the speakers and the listening position to create an equilateral triangle. So in the average listening room or living room, separate the left and right speaker by ten feet and then place your favorite easy chair ten feet back and centered between the two speakers. Keep the speakers at least two feet away from the front wall and the side walls of the room (unless the manufacturer advises otherwise). If there are windows in the room, window treatments are essential. Heavy, sound absorbing fabric is best. The room should be carpeted, wall to wall, if possible, however, a large area rug is doable. All of the above is generic but effective.
More sophisticated room tuning elements can include wall, ceiling, and corner acoustic panels that can be hung like artwork, with picture hooks and similar attachments. The ceiling and corners are trickier and will require Velcro and similar fastening systems. The acoustic panels are available in many sizes and shapes. Most are made from lightweight foam and/or fiberglass and are fabric wrapped. Many colors including custom ones are available from high-end, A/V specialty dealers. The placement of the acoustic panels is somewhat critical and should be selected based on the advise of your a/v specialist. The best a/v specialist will use test equipment and software to measure the room tuning response and base the selection of panels and placement on those measurements.
Another common room tuning element is the bass trap. In order to achieve a smooth and tight bass response in your listening room, bass traps can be deployed. The additional advantage to adding two or more bass traps to the listening room is to help provide an even level of bass in more than one listening position. (many living rooms will have a couch or loveseat instead of a single chair in the listening position). The bass traps vary in design and appearance and are frequently placed in the front and rear corners of the listening room. Some types basically appear to be a fabric covered cylinder, that could support a vase or plant. They also come in many diameters and heights and colors to suit the acoustic environment.
The best and simplest way to complete the process of room tuning is also the most fun. Listen to your favorite music and note the before and after results that you are hearing. Don’t forget to use the highest quality music sources possible. Don’t use MP3 compressed music sources. The best choices for the evaluation process are vinyl, cd, or uncompressed digital music files. And don’t be afraid to tweak! Move your chair around a bit. Move the speakers forward and back. Toe them in and out. You can also move the bass traps and acoustic panels around. Don’t be afraid to experiment. I will address surround sound and multi channel system tuning in a future PAC article.