The only real advantage to having a separate amp for the subwoofer is that you could probably come up with more wattage for your subs

Another advantage of having a separate amp for the subs is having separate gain controls, unless your 5/6 channel amp does already have its own gain controls for the sub channels. It is nice to be able to optimize your bass and sub-bass separately from the "main" frequency ranges.

tanstaafl.

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