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Background, desciption and other information:
November 2023: The trumpet straight mutes are all checked for good tuning, and I am quite confident that these sound good. I have made some with three corks and four corks. I think the four cork ones stick the the bell better, thus safer to use.
Trumpet straight mutes in the "blonde" wood are $35 each or 3 for $100
I can make them out of a very aromatic cedar for $40 each and the tone is possibly warmer.
The French horn mutes are now
child proof and tuneable. Child proof in that if someone drops something in your mute, you can pull the tuning tube and easily shake anything out.
They are tuneable using Mr. Burdick unique "Poor Richard's" sliding tube inside the tube design. YOu cna pull out the main tube and slide the inner plastic sleeve to where it works best.
Richard now has his final design comeplete A large French horn possibly not for smaller horn bells. He makes them in Cedar ($90) or stained quality plywood $80)
<video the sound of the cedar or plywood>
How Richard's "Poor Richard's Tuning System" works
How Richard's Ajustable wrist string works
mutes are somewhat harder to make. Prices vary from $40 to $85 depending on type of wood, and quality. An average high school student can use the cheaper ones. Ones with a string for the wrist cost $5 more. I have tried many different subtle variation of the horn mutes, so a player would need to bring a horn to my house a try different mutes to find the most suitable one, especially since bell sizes vary a bit.
Richard shows off 7 of his mutes:
Mid December comments:
I am doing a tube insert into the top so it can be slightly tuned, or the tube can be shortened for flat or replaced if sharp. I am redesigning the tube right now. 
For the string I was putting two beads on the string to adjust the length, but it got caught in my horn the other day, so maybe I'll just add a string and the player can tie a knot to adjust the length . . I'm working on them about a hour a day. My favorite wood is the cedar. See the picture.
It's your responsibily to make sure the insert tube is in seculrly, boxing tape can be wrapped around the tube to make it if more tightly. Check that you string is glue in sercurly once and a while so the string doesn't come loose couasing a big clunky sound durrring a concert.
If you drop your mute, It's not my fault.
Be careful the the "Poor Richard's" tuning tube is not to far our into the mute. I have not yet experience one commming out inside the mute, it might be hard to get out
