Marty Kasprzyk

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About Marty Kasprzyk

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  • Birthday 06/02/1945

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    Olcott, NY, USA
  • Interests
    Wine making, gardening, dog training,

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  1. I'd make a 5 string violin out of it.
  2. Thanks for the kind comments. The only recording in the public domain that I know of is the 2016 recording "Elias Goldstein Demonstrates 17 modern violas at the Oberlin Music Festival" if you do a Yahoo search, or "Modern Viola Demonstration" on YouTube. A good player (Elias) can make anything sound good. The important question is: How hard does he have to work at it? You might notice Elias is a short fellow and that the chin rest was way too high for him (I have a long neck) and playing was a struggle for him.
  3. Looks like great fun! Are you going to antique it or will you leave it looking newly built?
  4. If the back is left open you won't need the f holes. But if you want to easily drain the tub a plumbing valve could be used.
  5. I've gotten most of my Paulownia from: Groff & Groff Lumber 858 Scotland Rd. Quarryville PA 17566 1-800-342-0001 717-284-0001 I've use Paulownia for all my top and back plates, the upper and corner blocks, and the chin rests. I have also used it in the past for the ribs but I have recently switched to 0.8mm thick 3 ply birch plywood for the ribs because it is so tough and easy to bend. I have also used Paulownia in the past for once piece fingerboard/ necks for violas to reduce the instrument's weight as much as possible. I had to use interior graphite fiber tubes to stiffen it. Recently I have been thinking that the fingerboard and neck should be heavier so I've been using mahogany instead. I'll probably go to even more dense wood in the near future for violins for acoustic reasons. My one piece fingerboard/necks are simply butt joined onto the top surface of the upper bout with a screw coming up through a hole in the back plate. I can quickly switch fingerboards/necks to do experiments.
  6. I think there are two different markets for smaller viola. One market is for injured players who have been using large violas a long time and who now want an easier to hold instrument. They are used to the fingering with long string lengths and don't want that to change. Nor do they want a decreased sound output. The second market is for smaller players whose fingering might benefit from using a short string length. The "saddle to nut" distance is a useful measurement of viola size. But I've never seen any published data on other maker's violas. I suppose you could generate this measurement by scaling photos. The saddle to nut distance should correlate with the player's arm length which in turn is generally proportional to the player's height. I suggest holding the viola by the neck above your head such that it hangs vertically downward from your straight extended arm and left hand such that its lower butt (I meant to say "bout") is right in your face. The ideal viola size should place the saddle between your lips. My larger viola (shown in the photo) is comfortable for me to hold and has a saddle to nut length of 57 cm and I'm 72 inches tall (sorry for the mixed length units). The smaller viola has a saddle to nut length of 54cm. If a simple proportion is used this would suggest that a player 68 inch tall would find this viola is also comfortable to hold. Shorter players would benefit from even shorter saddle to nut lengths. But violas this small require shorter string lengths than my usual 378mm length. I've made real short violas with a nut to saddle length of 48.5cm ( violin size) which would be suitable for players about 60 inches tall. Standard violin A, D, and G strings are used and but short scale C strings are heavy, floppy and difficult to play well. Sometimes it has been suggested that small violas be made with deeper ribs to increase the instrument's volume in order to get a low A0 frequency. However deep ribs makes it difficult for the left hand to reach around the upper right bout for people with small hands. Also the lower bout's increased height might be uncomfortable for players with short necks so increasing the rib height at the top and bottom ends of the viola is not helpful for player comfort.
  7. Attached is a photo of 15 and 16 inch violas which shows they have the same 378 mm string lengths and the same middle and upper bouts while the smaller one has a shorter lower bout. Players do appreciate the shorter lengths. The also very much like their lower weights. The 15 inch viola has a total weight of 428g and the 16 inch one weighs 462g. Both of them have built in shoulder rests. The stress on the player's left shoulder muscles is proportional to the product of the instrument's weight times its length (torque) so reducing both the length and weight is helpful for reducing injuries.
  8. Don mentioned that he tries to keep a long string length and I very much agree. Short scale strings are often have lower tension than the longer ones. Since the instrument's sound intensity is proportional to string tension a short string will inherently reduce the sound output. "Go Practice" recommended using heavier tension (stark) which does indeed help increase the loudness of a short instrument but these strings also have increased mass which makes them less responsive during bowing. I also suspect that this might make wolf notes more unmanageable. So if you're designing a new short viola I would follow Don's advice of keeping the string length long. I shorten only the lower bout length when I make short violas such that the left hand/upper right bout feel and fingering doesn't change. The classic neck/upper/lower bout proportions are all messed up but after all it is just a viola.
  9. Maybe Mantegazze was the real master behind all this.
  10. My niece must weigh around 220lb which is way past what her limit should be. Her Belly is too thick. But she's a great and kind person so screw the relative weight idea.
  11. About fifteen years ago I wondered why violins used arched plates whereas most guitars used flat plates. I have now made 22 differently designed violins and violas using flat plates to see what problems might result and occasionally I've shown photos of these on MN. These have been reinforced on their inside surfaces with various lattice bracing schemes often used in guitars. The brace number, width, and height in both the longitudinal directions and cross directions can be varied independently thus the longitudinal to cross direction stiffness can adjusted over a very wide ranges to see what happens. This can't be done with standard arched plates. Reducing the cross direction stiffness (lower and fewer cross braces) increases loudness but excessive reduction increases wolf note severity. This is similar to what happens with over thinning arched plates. But this can be then corrected by adding more cross braces afterward and many back and forth brace change iterations can be easily done. It is expected in new product development engineering (like evolution in nature) that design changes will lead to a convergence to a desired goal optimum. However my instrument's sound characters seems to be diverging and my results keep on getting wider and wider. In vibration systems this is an "under damped" oscillation and in human behavior studies it would be credited to a scatter brained kid not having sufficient adult supervision (damping).
  12. I'm sorry for the brusk response. You had an interesting question and I should have given you a more serious reply. I'm often too wordy so I just picked up something from page 6 of the attached paper. If I was me I would use the same arch height and shape that I had used in the past so I could see the effects of using the really dense wood. (the sentence was supposed to start "If it was me..." but I mistyped it as "If I was me..." which inadvertently revealed the deleterious effects of prolonged exposure to violin making frustrations on mental health. Different plate thinning strategies 7_25_2019 .pdf
  13. Increased moisture content will make your eardrum skin not only heavier, but also more flexible. Your hearing has changed. Stop blaming the violin.
  14. I have the opposite opinion. Three 13's violin symptoms indicate low output in the lower ranges. A high bass bar and /or thick plates increases the frequencies and reduces the amplitudes of the lower resonances. So I think the plates are still too thick and/or the bass bar is too high. But as I was alluding to earlier, some different sound post positions should be tried first because those changes are reversible.