Marty Kasprzyk

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About Marty Kasprzyk

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    Enthusiast
  • Birthday 06/02/45

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  • Gender
    Male
  • Location
    Olcott, NY, USA
  • Interests
    Wine making, gardening, dog training,
  1. opinions of Milo Stamm bridges??

    The laser cut bridges I've seen have black edge surfaces. Perhaps many companies use water jets or CNC milling machines. Lasers might be great for cutting f holes in a few seconds.
  2. Instrument documentation photography

    On the other hand, should the violins be hung a little higher?
  3. Instrument documentation photography

    Is your camera tripod too high? My impression is that the camera is tipped downward a little. I see a lot of the upper surface of the bridge in the photograph. The lower portions of the back's C bouts are also visible. Should the camera be a little lower?
  4. Strad (and other) models database?

    I draw my outlines very carefully and cut the mold as close as I can and then bend the ribs as close as I can and put the whole thing altogether and it isn't close anymore to my starting drawing. This sets up an internal personality conflict between between being a "let it rip" vs. control freak.
  5. Secrets in the wood (Stradivari's maple)

    The damping qualities of spruce might be important for violin tops. The below reference describes how treating spruce with pernambuco extracts reduces damping If the old Italian master treated their wood is some manner it would be helpful to discover what they they did to avoid repeating it. Journal of Wood Science December 1999, 45:470 Vibrational property changes of spruce wood by impregnation with water-soluble extractives of pernambuco (Guilandina echinata Spreng.) Authors Authors and affiliations Masahiro Matsunaga Kazuya Minato Fumiaki Nakatsubo 1. Original Article Received: 28 January 1999 Accepted: 24 March 1999 22Citations Abstract Sitka spruce (Picea sitchensis Carr.) was treated with water-soluble extractive components of pernambuco (Guilandina echinata Spreng. syn Caesalpinia echinata Lam.) by two methods: impregnation under evacuation using an aspirator and repetitive surface application using a brush. The influence of these treatments on the vibrational properties were examined. The loss tangent (tan δ) of the impregnated specimen decreased, up to nearly a half of its original value, with increasing weight gain. It is suggested that the decrease in tan δ results from impregnation of the extractive components into the amorphous region of cell walls, forming secondary bonds between matrix substances. The surface application of the extractive components, on the other hand, hardly brought about the desirable change in vibrational properties. Key words Pernambuco Vibrational property Extractives Impregnation Musical instrument Part of this work was presented at the 47th annual meeting of the Japan Wood Research Society, Kochi, April 1997, and the 48th annual meeting of the Japan Wood Research Society, Shizuoka, April 1998
  6. Integral bassbars

    An argument was that that the tapered upper bouts were to achieve optical effects to make the side view less parallel: Antonio Pace, "Bee in a Foxglove bell: Historical and cultural perspectives on the stylistic quandary of the present-day violin maker" Catgut Acoust. Soc. J. Vol. 1, Nov. 8 November 1991 "The slight diagonal introduced in the upper bout by dropping the ribs height has the effect of reducing the visual height of that bout to that of the lower bout."
  7. Secrets in the wood (Stradivari's maple)

    If low wood damping is important for violins then the attached reference on treating spruce wood might be helpful: fulltext.pdf
  8. Basic Acoustics Resource

    A lot of things (racing: sailboats, bicycles, cars) which are supposed to move quickly are built to be as light as possible and they're often at the hairy edge of falling apart. A high failure risk is acceptable if it gives you a competitive advantage. Other things (buildings, dams, bridges) which are supposed to just stand there forever can be made more massive and have to be extremely reliable. Both of these cases can benefit from very good structural engineering and they just differ in the probability of failure that is acceptable and cost. So student violins are appropriately heavy and can withstand some abuse and while solo violins are lighter and often need bandages. If an old violin doesn't have all kinds of repairs it probably doesn't sound very good or it hasn't been used much.
  9. Basic Acoustics Resource

    I recommend the following fairly recent books: Michael F. Ashby, “Materials Selection in Mechanical Design, 4th edition”, 2011, Elsevier This book shows why various materials are chosen for different applications and how the materials are compared. I gives an easy to understand explanation of physical properties (strength, stiffness etc. we often discuss for violins) and how they are used. Neville H. fletcher, Thomas D. Rossing, “The Physics of Musical Instruments, 2nd edition”, 1998, Springer The first part of the book gives a background of vibration mechanics and mathematics. The remainder portions describe how different classes (wind, percussion, string etc) of instruments function. Thomas D. Rossing, editor, “The Science of String Instruments”, 2010, Springer Chapter 13 on violins was written by Joseph Curtin and T. Rossing and it gives a good overview on how violins function. Eric J. Heller, “Why You hear What You Hear, an experimental approach to sound, music, and psychoacoustics”, 2013 Princeton University Press This is a really great book for describing how sound is produced and heard without using hardly any mathematics. It has a chapter on the violin but everything else seems interesting too. For articles I suggest: (which is attached I hope) Colin E. Gough, “Violin Acoustics”, Acoustics Today, summer 2016 volume 12, issue 2, Acoustical Society of America Besides giving an excellent description of how violins work it gives many references if you want to further your reading. Gough.pdf
  10. Basic Acoustics Resource

    Yes but you should specify what time period you want to hold the shape. If at least 300 years is a reasonable then the Huberman thickness, arch and wood all apparently work well. If you want yours to last even longer then I agree it's a good idea to make them thicker.
  11. Basic Acoustics Resource

    The side view cross section view of the Huberman shows that the sag in the middle portion of the longitudinal arch makes that portion nearly horizontal. This may or may not be detrimental to the violin's sound character. The attached paper gives some evidence that a long horizontal arch produces a "bridge hill" increase in sound output at about 2.5kHz which is often found with good violins and absent in poorer ones. Perhaps this creep deformation was actually good and maybe it's a mistake to prevent it by making the center portion of the top plates thick. vibsys_2016-ch19.pdf
  12. Basic Acoustics Resource

    Just out of curiosity: Why didn't you include violin outline shape and size as variables? Strad made many variations of these. Why can't we?
  13. Basic Acoustics Resource

    I forgot to mention that I use 0.8mm thick 3 ply model aircraft birch plywood for the ribs. Its more crash resistant than curly maple.
  14. Basic Acoustics Resource

    Its not clear to me that the "best" wood for violins is also the best wood for violas. Violas make some lower pitch notes (C string) than a violin but they are only marginally larger. So you could argue that you should make the plates thinner, use lower arches, and/or lower speed of sound wood than what violins use. On the other hand nobody agrees what violas should sound like so it probably doesn't make much difference how they're made.
  15. Basic Acoustics Resource

    I use it for my tops, backs, fingerboards, necks and blocks of my violins and violas but most people say they're really not violins and violas.