In the following video, starting at about 6:00, Stephen Williamson of the Chicago Symphony talks about his strategies for breaking in reeds.
I recently started preparing my reeds according to this method, and the results have been impressive. Before sanding my reeds, every reed I played would have one of two problems. It would either possess a good resistance and sound rich in forte but fuzzy in piano. Or it would be too light and sound great in piano but pressed in forte. However, now I am able to get reeds that are both rich in forte and flexible and pure-sounding in piano.
Here are the basic principles for the method:
1. Use very fine sandpaper (I use 1200) to lightly sand all of the surfaces of the reed without damaging the tip. When you sand the underside of the reed, you must tilt up the back of the reed so that the tip is flush against the reed plate. That way you don’t chip the tip of the reed when going over it with sandpaper.
2. Wet the reed and play the reed for only about 10 seconds the first time. Let it dry out before sanding it and playing it again. You sand the reed before every time you play it. Roughly double the time spent playing the reed each time. My break in period usually goes like this : 10 sec, 20 sec, 1 minute, 2 minutes, 4 minutes, 8 minutes, 15 minutes. By the eighth time I play the reed I am up to 30 minutes. I consider the reed to be broken in at this point. It usually takes me about four days to get up to 30 minutes of playing per reed.
3. Keep track of whether a reed is light or resistant. If it is resistant, keep using the sandpaper. If it is light, switch over to normal paper for the sanding.
4. Not all of the reeds you prepare in this way will be good. Stephen Williamson said that he gets around 8 good reeds out of a box. I get usually 4 or 5. But even this is not so bad.
Some observations from my own personal experience:
Stephen Williamson uses really hard reeds. Before starting this method, I used Vandoren traditional 3.5 reeds with my mouthpiece. In the last two weeks, I have broken in both 3.5 and 4 traditional reeds in this fashion. Most of the strength 4 reeds were too hard. I have two excellent 4s, but now I am only breaking in 3.5s and just sanding them less than I would 4s.
Sometimes I find that the middle of the reed dries out while I am playing. You can usually see this when it happens, as the tip will look wet but the area over the window of the mouthpiece will have a different color, indicating that it is dry. A reed that gets dry like this will start responding funny, but simply wetting the reed again will usually be enough to return it to normal.
Keep using fresh sandpaper! The sandpaper will show some wear after a few reeds. Move to a different part of the sandpaper to ensure that you continue to get an even sanding.
Try to do the same number of strokes on all sections of the reed.
Don’t dry the reeds upside down. The tips will become wavy. Dry them in a reed case that allows air to circulate underneath them.