How to set up 2.1 please help?

Hi, I hope someone can help me with this.

I am running cubase 7.5 64bit on an i5 PC with an RME multiface.
I have 2 active monitors (left and right) plugged into outputs 1 and 2 on my audio interface.
I have an active sub plugged into output 3 on my interface.

Could someone outline the steps to set up a 2.1 monitoring option in the cubase control room for me please?

If needed I have an old version of Voxengo BMS (1.1 I think), which I have used in the past on a normal output channel. Can’t remember how I made it all work though, except that it seemed simple at the time (think I cheated with a surround master track)… I was running cubase 4 or 5 back then I think…

Any guidance would be much appreciated, as it’ll save me farting about for hours. Can’t make much sense of the manual. I thought I had a plan to get it working straight out when I went into the studio with a client the other night, but it didn’t work for me and I have to give up pretty quick to save face…

Cheers all

Mike

2.1 is meant to be used (active monitors) through the connections of your sub. The sub wil filter the sound that passthrough via the outputs to your active monitors, the filtered sound doesn’t have the frequencies the sub will be outputting and avoiding that the low frequencies are amplyfied by the sub and your monitors giving phasing problems or just to much low-end…

However if your sub only has a input and no outputs, search for a 2.1 plugin that you can insert on your masterbus. The 2.1 plug will do the same as mentioned first in this post.

Google: kellyindustries.com

Or this one: Bass Management

By any means do your own research because I just searched some but do not have any interest to check-up the found info as I have a active sub with filtering a pass thruogh connections for my monitors, the whole management is done in the sub itself.