The manual says that I need INPUT of 2KOhm impedance.(page500-13) I'd like to hook up an old boombox for the music source. I thought the speaker output on these was around 8Ohms so I have no clue how to hook this up. Would appreciate anyone's help and advice.

Can I just plug in where headphones go on the radio and punch those 2 wires down to pins 42 and 17 on the J1?