Soundboard contruction methods/ Ravenclaw?

[Michael Spreeman]

Hmmm, Ravenclaw, um, ok.
 
I checked the archives for remainder of this post, but only found it as it appears below.  I'm not sure if there was a question in there somewhere, but you're welcome to ask away on list or privately.
 
I've been out of town and returned to the 200+ list emails and wanted to mention a couple of things about the crowning method threads. 
 
In the article mentioned above, I stated the crown of my boards to be above 25mm.  Then I discovered "the list" and met the likes of Ron N., Del, Terry, Dale, the various David's, etc.  Ron was kind enough to spend countless hours off list discussing the different types of crowning methods and the conversations began with something along the lines of "25mm of crown,  hmmm, sounds to me like you have a whole lot of compression in that board!" (paraphrased version with numerous definitive superlatives excluded).
 
One of the results of these conversations was an awareness that intuition can often be flawed (paraphrased version with numerous definitive superlatives excluded). Ron informed me of the experiment which indicates that a rib is not a buttressed arch, much to my horror, amazement, and eventual acceptance. One of the comments posted about Ron's experiment was that it lacked credibility because it was performed on only one rib with a small piece of soundboard material. Being lazy and given the fact that I had a soundboard available for experimentation, Andy and I repeated the experiment with the soundboard. We placed the crowned board on the floor in a mocked up immovable frame encasing it.  Andy then stood on the middle of the board while I watched the edge closely to see if it would expand the framework. As I watched the edge of the board, it rolled upward and inward, away from the frame, proving Ron's experiment to work on an entire board.
 
Another result of the conversations is that the current 275 we are building has a hybrid board with more rib support and less compression.  The piano is not strung yet, but the board is glued in and has more boom and resonance than any board I've done to date.
 
Soooo, although personalities may collide and feathers may get ruffled from time to time, I would like to proclaim viva la list, and thanks to Ron and those who are willing to take the time to give freely of their knowledge base and skill sets both on and off list.
 
 
                Michael Spreeman http://www.spreemanpianoinnovations.com
On Jan 24, 2008, at 11:00, pianotech-request at ptg.org wrote:
I noticed a while back an article about the Ravenclaw (?) grand being built...
_________________________________________________________________
Connect and share in new ways with Windows Live.
http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_012008
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20080124/e9c40288/attachment.html