In order to avoid buying a new mixer, which I really can not afford, I am
considering passively combining 2 balanced signals (specificallay the
output of Yamaha TF1 modules). I know for un-balanced signals you use
resistors to isolate the two sources. Is a similar approach possible for
balanced signals? If so what issues might arise? I would really only be
doing this while writing and not for any serious recording.

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