Magnepan is a high en audio loudspeaker manufacturer in White Bear Lake, Minnesota, USA. Magnepan's speaker design, sold under the brand name Magneplanar, differs from that of conventional speakers in relying not on cones mounted in a box but on a planar system mounted in a panel. A Magneplanar's reproducing mechanism comprises thin conductive strips attached to a thin sheet of PET film residing in a magnetic field created by a grid of permanent magnets. When an amplified signal is applied to the strips, the resultant electromagnetic forces react with the permanent magnetic field to vibrate the PET film sheet, which projects sound as a dipole. In principle, this approach relies on the same concept as a voice coil-driven cone speaker, but in a Magneplanar speaker the "voice coil" is applied flat directly to the radiating surface. The most frequently claimed benefit of this design is the creation of a sharp, precise, and 'large' soundstage through an extremely short response-to-signal time. Its most frequently cited disadvantages are relatively low sensitivity and difficulty, given the absence of a box enclosure, in reproducing very low bass frequencies, leading some owners to use their Magneplanar speakers in conjunction with subwoofers.