Hi David At the risk of reviving a discussion held here some years back with one Frank Weston, I would point out that there is little tension anywhere in the soundboard CC assembly. If you meant by "tension", the more general "stress" then I understand your question below, and indeed it is exactly these kinds of questions I still find a satisfactory answer in lacking. One gets quickly into the discussion of just what vibrational activities are involved in causeing the exact transverse vibrations from the soundboard that sets the air in motion. If one takes the view that it is only the particular combination of stiffness and mass on the part of the soundboard that governs this output... then one quickly would be forced to conclude that the RC board is preferable due to its ease of construction and predictablity visa vi the CC board. However.... I have difficulty accepting without further ado, the a panel which is under large compression and otherwise has identical stiffness to mass relationships as another panel without said compression (if that equality is even possible to begin with) will perform equally or even nearly so from an acoustical output point of view. Of course my difficulty in accepting this does not mean that it is not so... but if it is then there must be a fairly easy to follow rational / explanation for why it is so... and so far I have yet to hear one. None of this btw is meant to infere the superiorty one way or the other of one type of board over the other. Its only meant to point out that the different methods most likely do indeed result in differing acoustics. Which of these any particiular person finds preferable is an entirely different subject.. yes ?? Cheers RicB I have a related question about downbearing. It would seem that a CC board prior to the application of string bearing is already under a certain amount of tension due to the crowning process as compared to a RC board. That being the case, and if a certain amount of tension/stiffness is a goal common to both types, might it not be the case that the amount of bearing required in a RC board would be greater than in a CC board to achieve the same tonal output. David Love
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