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+--- Thread: Stressed wood vs unstressed for sound (/thread-190.html)
Stressed wood vs unstressed for sound - jtkung - 04-12-2017
I was wondering recently the difference in tone between acoustics where the top is stressed a lot due to the string pull as opposed to a design where the string tension is alleviated somewhat using much stiffer components or internal bracing, and the top is not as stressed. The reason being that if the sound produced is due to the string vibrations downward force through the saddle and bridge to the top, then if the top is more stressed laterally, then it may exhibit more movement vertically.
The electrical analogy is something in circuit engineering called bias point. For example, a transistor is DC biased at a point where it operates in a specific range and any AC signal applied on top will exhibit characteristics based on the DC operating point. It could be higher or lower gain, linear or non-linear. For the acoustic guitar top, the stress from the static string tension can be considered a DC operating point, and when you pick the strings, this AC signal is the string vibrations.
It would be interesting to see tests done on top deflections on stressed and unstressed top wood to see if this makes a large difference. I suspect this is why bracing designs can make a big difference in the acoustic sound, along with the top carved design and thickness.