MIDI Solutions Quadra Thru Processor The MIDI Solutions Quadra Thru is a 1-in 4-out MIDI Thru Box. All MIDI messages appearing at the input are sent to all 4 Thru outputs. Active circuitry cleans up any skewing of MIDI data bits that has occurred at the input, insuring reliable operation in setups that require daisy chaining or long cable runs. The Quadra Thru is MIDI-powered and requires no batteries or power supply to operate. A MIDI indicator LED lights up when the product is powered and flashes when MIDI data passes through it.