The Autocom is a compressor, the ART is a preamp. They do different things. They are both pretty poorly made and do their respective things pretty badly. In particular, they both are fairly noisy. What kind of interface/preamp are you using right now? The AT-2020 is a pretty good budget mic and should sound fine going directly into the preamp in your interface. Does it?

i have the 2020 going into a roland cdx-1 8track digi recorder, no preamp on it, i thought the autocom would help that but you have clarified that for me, i assume i would need a preamp to remove the hissing sounds emitted by the microphone

No...
Your korg has a built-in preamp. It is not possible to run a microphone without a preamp.(there are exceptions to this rule, but not as far as this topic is concerned)

You're trying to run the mic into the Behringer, then into the Korg? This won't work.

The compressor should go AFTER the preamp, not before it. Otherwise, your compressor's doing absolutely nothing - there's not enough incoming signal to trigger the compressor to actually compress.