Starting Over

Jul 1, 2007 12:00 PM, By Nick Peck

           

Acoustic Approaches

To quote an oft-repeated aphorism, the single biggest sonic improvement to your tracks and mixes comes not from a new microphone or signal processor, but from tuning the room itself. Properly placed absorption, which particularly covers the low frequencies, is a critical aid in making mixing decisions that will translate well. Although complete coverage of room acoustics is beyond the scope of this article, there are a few things to keep in mind.

It is important to understand that surface treatment is not effective for soundproofing: it is used to balance frequencies and control reverberation time within the room. Surface treatments fall into the category of absorbers, which absorb particular frequency ranges of sound waves, and diffusers, which scatter sound waves.

Diffusers can be effective on the rear wall of a smaller space but are generally lower priority than absorbers for the typical project studio. Bass trapping and broadband absorption, on the other hand, are things that no studio should be without. You can start by placing bass traps across all corners of the space, because this is where low-frequency buildup predominates. Although each room has different needs, you should place absorption to the sides of the mix position, in the front of the room behind the monitors, across the rear wall, and on the ceiling, if possible, halfway between the mix position and the monitors.

Absorbers can be made from a variety of materials, but semirigid fiberglass batts and rock wool are the most common. The fiberglass batts are a solid, dense version of the pink stuff you have in your walls. These batts are typically encased in a wood or metal frame and covered with an acoustically transparent cloth, such as burlap. The thicker the batt, the deeper the frequencies it is effective against.

Bass traps are simply absorbers that are effective at absorbing bass frequencies. There are several ways to construct bass traps, including using thick batts with an additional air space between the batt and the wall.

Outfitting a recording space with effective, professional treatment can be a somewhat pricey proposition — on the order of several thousand dollars to do a fairly large room correctly. However, an investment in these products ensures that you will receive expert guidance from the manufacturer and high quality.

You can also build your own absorbers and diffusers. Owens Corning makes a line of semirigid fiberglass batts — model numbers 703 and 705 are most frequently used for absorption. All the required materials are readily available. In fact, Ethan Winer of RealTraps has an article on the Web (www.ethanwiner.com/basstrap.html) that explains exactly how to build a bass trap this way. Before you get started, though, be ready for a bit of pain: the process of cutting fiberglass batts and gluing burlap to the surface is about as messy as it gets. Be sure you have a large work space, a ventilation mask, clothes you can throw away after the job, and a high tolerance for misery.

I built all the absorbers for my last studio myself, covering all the front and rear walls, the corners, and much of the ceiling space with 2-foot-by-4-foot panels. Because I was at the end of my budget, building my own was the right way to go, but it was an unpleasant and time-consuming process.

In my new space, I chose products from RealTraps (www.realtraps.com): four Mondotraps for the corners, three Minitraps for the front wall, two RFZ panels for the sidewalls, and a pair of Microtraps for the ceiling. Because the studio is in a rented space, I didn't want to mount the ceiling panels to the ceiling. Instead, I attached hooks to the joint where the walls meet the ceiling, and strung airplane wire across at high tension, laying the Microtraps on top of the wires. The RealTraps look far nicer than my homemade absorbers, and will travel with me throughout the rest of my career.

In addition, I purchased RealTraps stands rather than mounting my absorbers to the walls. That had three benefits: I didn't have to deface the walls, installation time was immediate, and, most important, the absorbers can double as gobos for tracking purposes. With this system, I have no need for a separate vocal booth: I simply move the panels into the middle of the work area, creating a temporary recording space. On a recent session, I placed a Leslie rotating speaker in the middle of my studio, put up some ribbon mics, and encased the area with four of the absorptive panels. The result was the best organ recording I've done yet.

Your recording space can be a beautiful, intuitive, and ergonomically effective place to make music. Designing it takes nothing more than a little bit of planning, a little bit of money, and a little bit of elbow grease. Decluttering the area, laying things out for maximum efficiency, having clean, well-thought-out cabling, and making the investment in acoustic treatment will give you a personal studio that you'll never want to leave.

Nick Peck (www.underthebigtree.com) is a composer-keyboardist-sound designer-audio engineer in the San Francisco Bay Area.