This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment ----- Original Message -----=20 From: Erwinspiano@AOL.COM=20 To: pianotech@ptg.org=20 Sent: January 06, 2002 3:24 PM Subject: Re: Stein grand unique board In a message dated 1/4/2002 1:54:17 PM Pacific Standard Time, = JIMRPT@AOL.COM writes:=20 Subj:Re: Stein grand unique board=20 Date:1/4/2002 1:54:17 PM Pacific Standard Time=20 From: JIMRPT@AOL.COM=20 Sender: owner-pianotech@ptg.org=20 Reply-to: pianotech@ptg.org=20 To: pianotech@ptg.org=20 Hi Jim ,Phil and list =20 I would have jumped in sooner but have been gone. I was hoping = this would generate this kind of discussion=20 I have no argument with the the physical law stated below but = let me suggest for the sake of discussion that the primary energy source = being considered in the pond analogy, the pebble tossed in, is the = initiator of the waves action. The primal energy source. In the = soundboard system the traveling wave set into motion by the hammer is = the primal energy source and as long as the string vibrates the waves = continue to radiate out from the primary energy source and dissipate = into whatever by absorbtion,friction,heat or moving air.=20 -------------------------------------------------------------------------= ----- I'll point out once again that the pond analogy is not a very good one. = These are surface waves while the motion of the soundboard--at least the = motion that is creating sound energy is quite different. The system is = vibrating as a unified whole. Perhaps Phil Ford and Charles Fredrick Stein has a valid point = that we should consider the reflective wave as of lesser importance, = though not unimportant, when designing a soundboard system, apparently = Charles did.=20 As Del has said the soundboard system functions as system and = what we seem to be doing here is consider the various individual = component aspects as to there contribution to sound production as a = system. Seems to me like a healthy thing for a think tank to do.=20 As long as there is any vibrations felt in the rim there are associated = energy losses from the soundboard. Whether you view this as energy not = reflected back into the soundboard or as energy losses from the = soundboard to a less than perfectly massive and rigid rim is = irrelevent--it is still reducing the sustain time of the system.=20 Another thought that occurs to me is, that however the listener = would describe the overall sound of the Stein system, that sound will = have to be partially ascribed to the lack of reflected energy from the = rim on the straight side and curved side of the rim even though we can't = dissect or isolate it. Alas another mystery.=20 How would you describe the function of those relatively thick ribs = that--unless I completely mis-read your discription of them--remain = solidly glued to the inner rim? Also perhaps the fact that all the end grain of the soundboard = panel is terminated at the belly rail, which as Del pointed out, adds = all the stiffness the trebles require to function. Afterall sound = travels along the grain faster than across. My deduction from all this = is that the tail end of the piano is not as drastically compromised by = having a pseudo free floating edge around the majority of its perimeter. = And I would suggest that this is not even close to being a pseudo = free-floating soundboard system. Free-floating means free-floating as in = not attached to the rim in any way. And those ribs being glued to the = inner rim are not at all free-floating. Nor is the soundboard system as = long as the soundboard panel remains glued to those ribs.=20 Del ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/44/51/62/63/attachment.htm ---------------------- multipart/alternative attachment--
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