How to create feedback on the Eleven Rack

[Bunglespice]

So far I'm loving my Eleven Rack! I'm just having trouble figuring out one thing: How can I create intentional feedback?
You know how when you have a lot of pedals and you're too close to the cabinet it starts to feedback uncontrollably when you aren't playing? An example would be Nirvana - they have a lot of songs where in the break of the guitar playing, it is just leaking out noises everywhere? I love that raw sound and wanted to use it for a current project, but I'm not sure how to replicate that without an extra cabinet and too much gain.
I'm just lazy and don't feel like micing up a cabinet just for 20 seconds of feedback, especially since it won't fit the sound I'm getting from the 11R.
Any suggestions?

[Benoni]

What are you listening through now? Can you turn up the volume, point the guitar at the source, like studio monitors, and make sure the gate is set low or off.

[Drew Mazurek]

How do you do it with amp? What Brian said.

[bredo]

Pure physics my friend............

[YYR123]

Hah, that's an additional add on. $99 for the feedback plugin :)

[elicious]

hah is right ; you nailed it…

http://www.softube.com/index.php?id=af

(…tho we never much liked this;
just have our gtr player walk up to the JBL's…)

[Bunglespice]

So simple that I somehow missed that. it's a bit more difficult to pull off like I want because I can't have the volume turned too hot because 11R regulates the input. But it does work. Thanks for the solution, guys.