Diamond Bass Comp: 18v power, how to use the red polarity cable???

Hey everyone, I'm trying to figure out how to power my Diamond Bass Comp with my main power supply that I use for the rest of my effect pedals. I know that the polarity of the Diamond Bass Comp is inverted compared to the most effect pedals. I also know that in the box of the Diamond Bass Comp there is a red cable that is supposed to be used for inverting the polarity. I've being trying to figure out how to use it because whatever I do and however I put the cables it doesn't work. I can't power it and I still have to use its own power supply. Can someone help me figure it out so that I can just use one power supply to power up my pedal board and not have two power supplies. Also because the cables of its original power supply is breaking and I can't really find another one. Thanks

 

Ok so I just have to put the red cable between the pedal and the other power cables that then goes to the power supply. Did I understand correctly? Tomorrow I'll try it out even though I think I already did. Thanks

 

I guess I didn't look that well but I just found out (and tomorrow I will check and try) that my power supply for all my pedals should have two polarity converter cables, so if the red cable that came with the pedal is really bad, I should be able to do it anyway with one of those two cables. Tomorrow I have to find the box and cables and try it out. Thanks for the tips

 

Problem solved. I found one of those converter cables that came with the power supply for the pedalboard and finally made it to work just fine. Plus I made order on the pedalboard and change the AC adapter since the cables were broken and the plug was always loose. Thanks for the help