Built by Allen & Heath, the Xone:PB is a 1U rack size passive interface box designed to provide a quick and easy solution to set changes in busy club line ups. The Xone:PB simplifies the task of connecting encoded vinyl replay systems to installed mixers without the need to re-patch. The outputs from up to four audio sources and the inputs to the mixer channels are connected to RCAs on the rear panel of the unit. The front panel connections echo the outputs from the audio sources on the left side, while connections on the right provide inputs to up to four external sources. Switches on the front panel select whether the mixer inputs are connected directly to the audio sources or diverted to the external sources, allowing very quick and simple interfacing to scratch amps or computer soundcards. The audio source connections on the front panel are duplicated, enabling two scratch amps to be connected to the same audio source for simple DJ handovers. Additionally, two switchable inverse RIAA filters are available to enable line level sources to be connected to the phono preamplifiers of the mixer, there is common mode noise attenuation filtering on all external inputs to help reduce laptop power supply noise, and an earth lift switch helps prevent ground loops.