<HTML>In a message dated 1/4/2002 1:54:17 PM Pacific Standard Time, JIMRPT@AOL.COM writes: <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Subj:Re: Stein grand unique board Date:1/4/2002 1:54:17 PM Pacific Standard Time From:    JIMRPT@AOL.COM Sender:    owner-pianotech@ptg.org Reply-to: <A HREF="mailto:pianotech@ptg.org">pianotech@ptg.org</A> To:    pianotech@ptg.org    Hi Jim ,Phil and list</BLOCKQUOTE>              I would have jumped in sooner but have been gone. I was hoping this would generate this kind of discussion       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.   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.       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.    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.        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.             Best        Dale Erwin <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px"> In a message dated 04/01/02 4:11:27 PM, fordpiano@lycos.com writes: << But I'm still a bit skeptical about the idea of waves bouncing back from the rim.  This is a variation on what I've been conjecturing about in previous posts. >> Well back to the pebble in the pond analogy....if'n y'all throws a pebble in da pond the waves will travel away from the pebbles impact point until they meet a point of resistance they can't overcome...at that point the energy will be reversed and a and a corresponding, and identical, wave will begin it's journey back toward the point of origination and any other point that the surface of resistant determines by the angle of impact. If the point of resistance is a rock cliff face the most energy will be reflected back to the impact point...if the point of resistance is  a pebble beach a very fragmented pattern will be returned...if the impact point is a wide bed of weeds most all the energy will be soaked up by the weeds and almost none, if any, will be reflected back. Energy works in the same manner in all mediums unless 'forced' to do otherwise by design. Jim Bryant (FL</BLOCKQUOTE> </HTML>