How do you hook up a Technical Pro RX504 integrated amplifier with a DVD player for your songs a computer with your karaoke and a Mackie 16 channel mixing board to sing through?

To hook up the Technical Pro RX504 integrated amplifier, connect the DVD player's audio output (RCA or optical) to one of the RCA inputs on the amplifier. For your computer, use a 3.5mm to RCA cable to connect the computer’s headphone output to another RCA input on the amplifier. To incorporate the Mackie 16-channel mixing board, connect the mixer’s main output (XLR or 1/4" TRS) to the amplifier’s auxiliary input or line input. Ensure all devices are powered on and set the appropriate input source on the amplifier for the desired playback.