DSP PRO HD iPad app, puts you in control of all the functions of the XFIRE AUDIO XFR DSP PRO, Digital Sound Processor. Intuitive, user friendly interface to tailor your sound system to your car. The app uses bluetooth to connect with the DSP and gives you the ability to map the inputs and outputs, set the x-overs, EQ, Dynamic Range Compression, Delay and Output level for each channel.