Check the listing for details. Radial BackTrack 2-ch Active Direct Box and Audio Switcher. Condition: New. Listed at 459.99 USD. Redundant Audio Switcher for Backing Tracks or Guitar Rigs Based on the 8-channel Radial SW8 but tailored to meet the needs of smaller acts and solo artists, the 2-channel Radial Engineering BackTrack manual audio switcher is equipped to receive two feeds of stereo audio and keep the music going even in the event of a failure. Whether you're feeding it redundant backing tracks from two laptops/mobile devices or signals from two identical guitar amps, the Radial BackTrack won't let you down. You can switch feeds directly from a switch on the back of the unit, or seamlessly underfoot via the optional Radial JR-2 Remote footswitch. Isolated balanced XLRs feed a mixer or pair of powered mains, and Dual 1/4" TRS monitor outputs assist with monitoring through stage wedges.