Technology / Home Audio / Isobarik: Sometimes spelled Isobaric, this is an enclosure design in which two or more Drivers are coupled together by a sealed air mass to operate as a single driver. With proper sealing and design, very impressive results can be obtained from an unusually small box. A popular version of this simply consists of two woofers placed over each other in a 'clamshell' design. The downside consists of the fact that it does require at least twice the amplifier power as would be needed for a conventional speaker, in order to be operated successfully.