theres nothing scary at all, we are just dealing with simple logic, out to in and in to out
bass: your sound source
ds1: your sound source processor
amp: your processed sound destination
bass(output)--->(input)ds-1(output)----> (input)amp
when you play the bass into the ds-1, you bass signal get process by the ds-1, this process signal get amplified through the amp and you can hear it.
the jack on your bass is the output, goes to the input of the ds1.
The processed bass signal(thru ds-1) goes to the input of your amp.