One of the coolest things I've seen in a while is the new TeaBagz panel from Modular Acoustics. It's a portable broadband absorber constructed of rigid fiberglass in a specially fitted "bag." The manufacturer sells TeaBagz assembled or as a DIY kit. When completed, each TeaBagz is 48''x24''x4'' and weighs about 10 lbs. You can mount one on a standard mic stand.
Acoustic designers use broadband absorbers to reduce unwanted resonances, tighten up the low end, and improve imaging. But they have other uses for recording. For example, TeaBagz are incredibly useful for providing mic separation when tracking full bands. Depending on placement, they can shield the mic from enough bleed to give you a fighting chance during mixdown. While tracking, players can still see and hear one another. In our live room, strategic placement of the TeaBagz can decrease natural reverberation, giving us as dead of a sound as we need. We attached Velcro strips down the long edges, allowing us to build walls and portable isolation areas with ease. We also used three TeaBagz as a portable vocal booth for location recording. See the Modular Acoustic's website for sample setups.
As I mentioned, you can buy TeaBagz assembled or build them yourself. We purchased the kits, which is great if you don't mind doing a little work. First, you need to purchase rigid insulation to fill the bags. Most people call this "700 Series" after the designation given by Owens-Corning for its line of rigid Fiberglas®. ("700 Series" is the "Kleenex" of this market.) However, several other manufacturers make similar products; other common descriptors are rock wool and mineral fiber. These products are typically not stocked by most home improvement centers. But don't worry. Insulation and heating supply houses often have it by the ton, as do suppliers of commercial building products. We were able to buy enough rigid insulation to fill eight TeaBagz for about $150. So for about $400, we put together a significant portable sound treatment system.
My only issue with the TeaBagz is the name. Of course, I hang around too many theatre types. Anyway, where was I? I can't think of a studio that couldn't use a set of these ingenious panels. From tracking to mixing, Modular Acoustics TeaBagz are a flexible, effective, economical way to improve the quality of your recordings. ($65 each plus S+H assembled, $30 per kit; www.modularacoustics.com)