Turn any stage mix into a headphone mix when you start using in-ear monitors now with the Sound Tap personal monitoring system. Sound Tap works with any stage setup. If sits between any mixing board or speaker. You can support both line level and speaker level inputs. It's as easy as: Tap (walk up to any stage or studio and tap into any audio source); Plug (sits in the signal path without affecting anything or anyone); and Play (adjust input level, volume & go). Features include: · Spike protection and active impedance matching · 20 Hz - 20 kHz frequency response · ~30 hours of battery life on a pair of 9V batteries · 1/8 inch. stereo headphone jack, 1/4 inch. Combo XLR