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(revised 10/2020)
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Guarnarie Plate Graduation Plans....in use 2009-present...
...Violin plate graduation, even of famous violins can be quite varied. However, I imagine this following information will yield consistently professional results which will survive in constant use for several hundreds of years.
  It is said that "good violins have been made for centuries that are 2.6mm thick'" for the top plate (spruce wood) and this is what I recommend now.
...My last three violins produce exceptional sound performance with these plate graduations.
...The back plate graduation is based on the analysis of the measurement of famous Gruanarie Del Jesu violins shown in the violin making book.
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...Click here to see details of Guarnarie Top Plate Graduation....That I am currently using.
...Click here ot see details of Gruanarie Back Plate Graduation...That I am currently using.
..See bottom of this page...
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... The outline plan is to make the back plate tap tone, when complete, to be between f and f# (below middle 'C' on the piano) with both the upper bout and lower bout matching and the lower bout tap tone of the top plate to also match the back plate. (the upper bout of the top plate will be a lower tap tone...more on this later).
...So the back plate should be completed out side ready for varnish and then the inside graduated to the plan shown (see link above).
...Next the top plate is completed with the inside graduated to an even 2.6mm. The lower bout tap tone of the top plate is measured and then compared to the back plate result with its initial tap tones (once evened out so that both upper and lower bouts match).
...If the back plate then is adjusted so that it is as close as possible to the top plate result and still be within the f to f# range (which is very important). The top late is then adjusted to match the final back plate tuning.
...At that point the back plate is ready to be joined to the rib structure and the top plate have its bass bar fitted and then its ff holes marked and cutout. At that point, the completed top plate is also ready for assembly {allowing for any ground treatment to the inside of the plates that may be desired to be added first.}
...At this stage, the potential of this particular violin is set, as it can be no better than the potential of the completed sound box.
..
..Current research (2017) strongly indicates that the wood selected will make a huge difference in the out come of your violin.
..I strongly recommend you only use wood of the proper Wood Tone and Rub Tone:
..For top plate (spruce) 198 HZ Wood Tone and # 22 Rub Tone.
..for back plate, neck and possibly ribs: 242 HZ Wood Tone and # 22 Rub Tones. Please see other areas to learn about this technique.
<<10/2020 note: Please also lookup information on "synchronous resonance" wood selection technique for matching the best wood pieces together for your next instrument.>>
 
David Langsather (c) 2017 Salem, Oregon USA
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...Click here to see specific examples of Guarneri plate graduation from the famous book (5 pages)...(1/2009)
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