Sent: Wed, Jul 14, 2010 7:37 am
Subject: Re: [pianotech] soundboard grain angle vs "faux"stiffness
Jim
One thing to keep in mind that any soundboard designer/makers on this list have decided what type of tone they are looking for and have experimented with designs that provide their ears with a very particular tonal envelope. It is very important to know what your clients taste are and if they are willing to trust you to provide them with that. There are a few other things to keep in mind.
My own B is a RC & S design that is un-characteristically not a pure Steinway sound and I Love it. Did I hear applause?
Andre Oorbeek was here last month and he said... "It does not sound Like a Steinway" and, "I have never heard a piano that sounded like that."....He loved it. He/we said its more a Steingraeber/ Erwin & Sons...with laughter of course. It's dark, powerful and voluminous and most have flipped out over its uniqueness but some are more found of a more open sound. The design spec: is a grain angle that follows the long bridge (approx 30 degrees off the long side) ,serious curved cut-off bar, small 4 note transition bridge, no ring bridge. Double wrapped mono-chords...no fish...complete with the Dennis Erwin racing stripe on the top.
The restored 1894 B sitting in the same room is a rib crowned design,with the grain angle 40 degrees off the spine as usual, with a short straight bass cut-off bar, disconnected ring bridge with 3 unions of bi-chords at the tenor break.. Double wrapped mono chords, original string scale with a Sitka board/ribs and 13 variable crowned radius ribs. It has a fantastic sound. By the way I love the sound of good Rib crowned board. It is a MAJOR upgrade from the old CC boards and in my opinion will have waaay more gas in the life span tank than a CC bd.
The 1894 B has a more traditional voice and it is very impressive and attractive sound both to me and many others. SO Viva la difference.
I say this for several reasons. Know your client. Know what they want, and know how much extra work the R & C boards & the amenities can be.
R C & S designs should cost the client more money for the engineering and expertise etc. and in this economy getting them to pay for it is tougher to do.
Extra work ie. the engineering, filling in all the rib notches and cutting new ones,fish,cut-offs, for newbies the risk factors etc. Also know that many folks will not want a re-whatevered Steinway no matter how well you did the work.
I encourage anyone to get in front of some of these pianos and listen for yourself. Pay attention to the features as I have mentioned in each and really listen. Get some one to play real music on these boxes and then play them yourself.
I know that David L., Ron N., Will T, Jude, David A. myself will all welcome studious listeners. This is an extreme advantage that most of us did not have before more examples were available. We just had to make them and see. It means traveling but its worth it.
The great thing about this list is any one can express their opinion on stuff and this is mine.
Ain't it great?
Food for thought
Dale S. Erwin
www.Erwinspiano.com
209-577-8397
-----Original Message-----
From: David Love <davidlovepianos at comcast.net>
To: pianotech at ptg.org
Sent: Wed, Jul 14, 2010 7:00 am
Subject: Re: [pianotech] soundboard grain angle vs "faux"stiffness
My current choice for smaller pianos is around 50 degrees, 55 degrees for a
B. Of those doing these designs I think 60 is more the norm. Some people
have gone to 70 degrees on a D (that I know of) but not on smaller pianos.
The choice of a greater angle is to stiffen the treble. The greater angle
has some cost in the bass thus bass floats tend to accompany those designs.
My choice to back off the grain angle has to do with trying to help the
stiffness in the treble without changing the character of the tenor. Since
I don't do full design changes on all pianos (meaning I don't always do a
bass float) making the angle too severe wouldn't probably be advisable in
those situations. The difference between 45 and 50 degrees is probably a
fairly subtle one and I have not done an RC&S board at 45 degrees. You are
right that the backscale concerns are to insure that the assembly has
freedom of movement. There is a difference between making the panel stiffer
and tying it down and making it immobile.
David Love
www.davidlovepianos.com
-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of jimialeggio
Sent: Wednesday, July 14, 2010 6:23 AM
To: pianotech
Subject: [pianotech] soundboard grain angle vs "faux"stiffness
I've been thinking a bit about how the calculated rib scale allows you
to design a spring with known stiffness, and have setup my spreadsheets
and belly experiments to predict and adjust this quantifiable
stiffness/flexibility (spring).
As has been mentioned, there are other parameters such as back scale and
grain angle, panel tapering or not tapering which also effect
"stiffness". I put "stiffness" in quotes because ribs design targets
and creates a spring while these other parameters, backscale etc either
restrict or avoid restricting that spring...they don,t create spring.
They are often referred to as having "stiffening" qualities but I'm
thinking that there is a structural and tonal distinction between
stiffening as the result of spring rate of a rib and "stiffening" as the
result of limiting movement of the rib spring.
David Love, it sounds like you've played around with various grain
angles on calculated rib boards.
Have you experimented with the traditional 45ish degrees, ie somewhat
parallel to the long bridge, board angle?
Most of the rc&s boards I seen or hear about assume that the slightly
greater 50-55 to more is an improvement, while some push 70deg. It
seems as if the tenor and bass would appreciate the near full crossgrain
effect of grain parallel to the tenor in the long bridge.
As in most belly issues, I suspect that the tradeoff was made to help
out the treble, ie keep the rib weight down in killer octave by
"stiffening" the board in that area.
Are there any calculated string load/rib scale folks working with low
grain angles?
Jim I
--
Jim Ialeggio
grandpianosolutions.com
978- 425-9026
Shirley, MA
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