I guess the trick is to use the shortest cable you can get. Although the gain might be sufficient to get it to where you need, the thing you lose with unbalanced inputs is the ability to reject induced noise and interference. But keep your cables VERY short (basically, straight from the mike to the input, no extra at all) and this shouldn't be the problem it might be using 25'+ cords...
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An arranger is just a tool. What matters is what you build with it..!