Ask a Luthier Codabows Instruments Links Pi Guitar String Band Contact
Return to questions listing:

Saddle Question

I am wondering if you could tell me about saddles?
What is the tonal difference from a saddle in the bridge or on the soundboard? I have a bridge that the saddle sits on the bridge and would like to set the saddle on the soundboard by scraping the slot to the board. What would you recommend and why. - Rick

Sound waves travel quickly through the hardwood of the bridge. The hardwood doesn't move very much and doesn't absorb much of the wave's energy. The bridge is a sound carrier. Sound waves travel slowly through spruce as the spruce vibrates madly, dissipating the wave's energy. Spruce is a tone producer. The analogy that I use is running down a sidewalk and running through a swamp. Running through the swamp is much slower, because your feet are moving the swamp as you run. Sound waves move quickly and easily through the hardwood of the bridge to where they meet the spruce sound board. The energy of the sound wave is dissipated as it moves the spruce, transferring the vibration to the air. So, the bone of the saddle carries the vibration of the strings to the bridge. The bridge is shaped to send the vibrations out onto the top to be transferred to the air. Trying to get a direct connection between the saddle bone and the spruce top ignores the vastly important function of the hardwood of the  bridge.

Another spot where the dichotomy of tone carriers versus tone producers functions is in the back and sides of a guitar. The most common back and sides woods are Rosewood and Mahogany. Rosewood is a tone carrier. Vibrations that come off the underside of the top, hit the back and bounce back up to the top. Rosewood guitars are louder and have a richer bass. Mahogany is a tone producer. Vibrations that come off the back of the top, excite vibration in the mahogany and are projected behind the guitar, and are not available to re- kick the top. So mahogany guitars are brighter with less power, but better note definition. The great flaw of guitars is that they are designed to project forward. Everyone can hear your guitar better than you can. Mahogany guitars have less of this problem that Rosewood guitars do.

Steve Mason

Return to Questions