Ebony bridge caps

[Ron Nossaman]

> There are a few problems I have with the theory of harder bridge cap
> material influencing the sound as described. 

I basically agree. If the maple cap is soft and compliant 
enough, or the pin fit is not tight at the top, allowing 
deflection with string vibrations, it's absorbing energy. New 
maple caps don't typically show these kind of problems, but 
I'm told by people who have had access to adequate measuring 
means, that laminated and very dense caps are somewhat less 
absorptive and lossy, though not necessarily audibly so. Make 
the cap less compliant without significantly increasing mass, 
and you'll likely find that it is the mass in the exotic wood 
capping that's making a difference - assuming there is an 
audible difference.

Also, there's a lot of talk about vibration in bridges. 
Consider that by the time a string at C-8 goes through the 
"pressure" half of it's fundamental cycle, the pressure 
impulse imparted to the pin by the string has traveled clear 
through the bridge to about 15cm (6") below the soundboard, 
and about a Meter along the bridge. Double those distances for 
one full fundamental cycle at C-8, and I wonder what 
vibrations there might be within the bridge that do anything 
at all of any importance that a harder wood cap will 
influence.

Ron N