In spite of the fact that the Michael Brecker/Brecker Brothers envelope filter sound is loved by horn players the world over, there is very little information about what settings (and what envelope filter) will get you there. Believe me--I've scoured the internet. It's not out there.
The most well known guy using the effect currently is Jeff Coffin, he of the Dave Matthews Band. He uses an older Q-Tron, and there's a picture of his pedal on his website so you can snag his settings. However, he seems to prefer it set so that the filter doesn't open all the way, which isn't really like the Brecker Brothers sound. I bought a newer Q-Tron and set mine up like his, but it wasn't until I messed around with it for an hour or so did I finally find was I was looking for. Here are my settings, in case you want a better starting place.
MODE=HP (high pass)
It sounds like this: