Brian
On the Echo, chuck it in a collet chuck and run a 1/4" bit real slow to clean out the air channel. Too fast and the drill bit can run of center, and I mean slow speed on rotation and slow in drilling into it. You will also need to open up the exhaust end start with a 1/2" bit and goes as far as you can with out getting the plastic too thin, then drop down with smaller bits, step drilling to the cork slot. I do not cut off the cork slot, I keep it so I don't have to use a castration band. For another version try a double reed, make the top reed a little smaller and different shape, don't forget to dimple it or it will stick. It will sort of look like a Syco tweety, and no I did not copy theirs, I made them like this for years before I ever saw a tweety. And yes anyone may copy me, I consider it public domain.
Marvin
