I've just spent an hour scratching my head after watching Craig Anderton's SONAR ADVANCED WORKSHOP segment on setting up a "Looper".  It is also explained in his SOS article here:  http://www.soundonsound.com/sos/oct12/articles/sonar-tech-1012.htm

I thought I had my signal paths, sends, etc., set up exactly as shown (although I'm using a Rolad Quad-Capture which only has Input/Outputs 1-2 and 3-4), but am getting no sound from the delays on the Looper Bus.
 
Then I see in the SOS article that the looper bus he is using "...output terminates in audio interface outputs seven and eight, which patch through physical patch cords into inputs seven and eight."  Took me an hour to realize that my equivalent Outputs 3-4 need a "PHYSICAL PATCH CORD", right?  There's not some "internal" connection between those inputs and outputs?  

Yes, you need to use physical patch cords to loop the output back to the input. It's a little inelegant but it's the only way I've figured out how to get really looooooooooooooooooooooooong loops.

Thanks, Craig.  Looks like this will be fun (but I sure did feel like an idiot for a while).  :-)

Hey, Craig. How are, ya? I'm wondering... I notice that a lot of the segments in the Advanced tuts have article counterparts on SOS. Do you have a list of those related articles somewhere? I've found watching the vid then working through the text version to be very helpful to learning those techniques. If not, that's cool. Just curious. Hope you've been well.

If you want really looooooooong loops would a long Monster cable work? 
 
 
 
 
 
 
 
Are we talking ground loops?

I think that would be long and overpriced loops, John. ;-)

looping huh ? Reyn is on point regarding that.. http://www.youtube.com/watch?v=PTSUR3RHh9M
 
he don't use sonar though (sorry )