I can't think of a single reason (in your situation, given your equipment) that you shouldn't choose balanced over single-ended; and not just for noise rejection (which shouldn't be that big a deal for just 1.5m anyway) but because you get so much more signal out of the balanced output of the preamp -- I think that would trump using a slightly less expensive (but good quality) balanced cable over a more expensive single-ended one.
OK, whose gonna take the first swing!?
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OK, whose gonna take the first swing!?
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