Are you planning to record the sounds from just the XD3 or the accordion as well? I don't know how modern accordions work: in other words, is there some sort of audio output or is it just an acoustic instrument, like the old Soprani or Scandalli I used to know? The question is relevant, because if the accordion has some sort of audio out then you need to connect the audio outs of both the accordion and the XD3 to the audio in of a mixer and the audio out of the mixer to the line/audio in of your sound card, in order to record the sound from both instruments. If, on the other hand, the accordion is like the old plain accordions, only with a midi out added, then you'll of course need a microphone to record its sound and the mic should then be connected to the mixer.
Sorry for asking such naive questions, but when it comes to accordions I am kind of lost, I guess.
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