not to sound like a know it all (it is up to you if you use compression), but I think it is a neccessary part of the production process. compressors smooth out your sounds! they allow you to hear the full sound (ie the low amplitude "tails" or quieter sections that you might not normally hear are brought out). I definitely notice a much fatter sound if I use compressors (and I use them on most things.) just my 2 cents though...
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