Good way to dampen tonearm?

I think that is a very bad idea especially since this would be permanent. What if it sounded like crap? You would be buying a new arm.

DAP makes a foam that can be cleaned up with water, but the other stuff (Great Stuff?) is polyurethane based, it is very sticky, and you need something like acetone to clean up. It might attack the coating on your wire and will certainly expand out of the tube and make a mess that will be hard to clean up. You will also have to compensate for the extra weight.

While I assume it is a dielectric (insulator) it's dielectric properties will be different than the one it replaces (air) and may alter the sound.

You will also be changing the effective mass and resonant frequency of the tone arm and your cartridge may no longer be a good match for it. Check out http://www.gcaudio.com/resources/howtos/tonearmcartridge.html

If you want to experiment I would go with the other ideas above that are easily reversed.

BTW dampen was used correctly in the original post.

damp·en
v. damp·ened, damp·en·ing, damp·ens
v.tr.
1. To make damp.
2. To deaden, restrain, or depress:
3. To soundproof.

Dampen is a verb and was used correctly. Damp is a noun or adjective so it is used incorrectly in the phrase "damp your tone arm."

Some shrink tubing has glue on the inside that is activated by the heat. If you try that make sure you get the kind without glue. It would also be hard to cut off without scratching the arm.

Semi, follow the link in my post above and it discusses the resonance inherent in everything and why it is important to have the resonance of the cartridge/arm combo at the proper frequency.

There are arms made of wood and carbon fiber BTW.

http://www.wilson-benesch.com/act_2/act_2.html

http://www.galibierdesign.com/prd_schroeder.html

I guess I need a new dictionary too.