IsoPads consists of 4 pieces of high density, low compression polyurethane foam, enough for two loudspeakers. Each piece measures 12.75" x 4.5". and available in two profiles. The IsoWedge is cut with a 6° slope and is intended to accommodate meter bridge or tabletop mounting where the monitor speaker will need to be aimed up or down for the best on-axis positioning. The IsoPlane is cut with a planar profile making it useful for isolating equipment that requires a level surface such as DJ turntables and CD players. IsoPads are used to counter the effects of vibration-loading, or the physical transfer of vibrations from one solid directly to another solid. In the case of loudspeakers, vibration loading occurs when speaker cabinet vibrations are transferred to structures that support the loudspeakers. Vibration-loading is perceived as an artificial boost of mid and low frequencies. The direct result of vibration-loading is that a listener will hear a combination of direct sound from the loudspeaker and the effects of structural resonance. They hear a frequency content altered by resonance instead of an accurate picture of what is actually on the recording. If that listener makes mix and equalization decisions based on what they are hearing, the mix will lack low and mid-range frequency content when reproduced on other play-back systems