About 3 years ago I had an idea that I'm pretty certain is an original one. Although very odd, this idea worked so well that I now implement it in many of my repairs. I'll outline this idea as a procedure to make it clear what I am doing and why. If anyone out there is doing something similar I will be happy to hear your thoughts.
The problem I was trying to fix when this idea came to me was a stuffy note on a Buescher Alto Sax. The note is the alternate or forked F#. The tone-hole for this F# on a Buescher alto is very small, so nearly every Buescher alto that I have played suffers from a stuffy F# because of it. Opening the key height makes the stuffiness better but it's still present.
It is not air that we are necessarily dealing with inside saxophone, rather it's a wave, and further it's a standing wave. Knowing this I still had the feeling that allowing more air to escape the tone-hole would improve the tone of this particular note. Considering ways to do this, I thought about adding a scoop of sorts onto the tone-hole that projected into the bore. Something like an air foil. I also thought about adding a vent
somehow to that area. Finally it hit me to try adding turbulence on a low level to reduce the overall turbulence experienced at that tone-hole.
I considered roughing up the tone-hole with sand paper. I tried this and worked a little but not great. I was surprised when it worked even a little. A little is better than nothing. I took the idea a step further and added a liner in the tone-hole made of sand paper. My thought was that this might work the same as the dimples do on a golf ball. By adding turbulence near the surface of the tone-hole, air might be allowed to rush out of the tone-hole more freely.
This theory is best understood when considering a large mass of air traveling over a surface. It the surface is smooth like glass, the air will encounter friction there and slow down. The air is slowed and continues to slow the air column around it. Consider that same mass of air traveling over a rough surface. The air that is directly in contact with the rough surface will whip around in turbulent circles. These circles of air act like a bearing for the rest of mass of air to travel over without friction. So adding turbulence actually increases the air flow. This is what I hoped would happen in the tone-hole.
After gluing the sandpaper in the tone hole and playing the note, I was amazed that it really improved the tone. The stuffy hissing air problem was nearly solved. Adding sand paper to the tone hole made a stuffy note much less stuffy.
I have also found that "The sand paper trick" works to take the fan or warble noise out of octave C that plagues so many sax players when playing at higher dynamics on instruments such as modern Selmer altos, vintage Conn's, vintage Bueschers and many other instruments.
Any tone that is stuffy can be fixed with this trick. However, I suggest searching for a solution such as mouthpiece, reed or key height before implementing this fix.
Here is how I install the sand paper. For ease of viewing, the work below is done on a horn without keys or posts. Of course, one would not need to remove this many parts when doing this simple job.
1.Remove the key
2.Clean the tone-hole clean with Alcohol
3.Cut a strip of sand paper
4.Apply contact cement
5.Glue the sand paper: It is not important that the sand paper match perfectly at the seam. Place the seam at the bottom of the tone hole. There are several pictures here to help you understand.
6.Press the sandpaper firmly on to the tone-hole
7.Apply super-glue to the sand paper (this makes it very permanent)
8.Cut the paper to match the contour of the body
9.Apply more super glue
10.Check that the paper is truly fixed
11.Clean the tone hole surface making sure it is not covered with adhesive.
12.Assemble and play
Best of luck to you!