Marty Kasprzyk

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About Marty Kasprzyk

  • Rank
    Enthusiast
  • Birthday 06/02/1945

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  • Gender
    Male
  • Location
    Olcott, NY, USA
  • Interests
    Wine making, gardening, dog training,

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  1. Marty Kasprzyk

    machine made violins also CNC "Betts"

    How is a cnc better than a duplicator?
  2. Marty Kasprzyk

    Congrats to all!

    I didn't win anything at the VSA competition so I went to the hotel bar afterwards and drowned my sorrow in beer. But I couldn't stop thinking about where I went wrong. Next time I'll try amber ale color for my violins.
  3. Marty Kasprzyk

    'taptones' of a unstrung violin in the white

    I'm not sure about this. It might be correct or incorrect. I agree a high amount of damping lowers the peaks but it also raises the valleys. Since any violin note consists of many harmonics some of these will fall near or on peaks while others will fall in valleys by chance. If the loudness (power) of a note is determined by some sort of sum of the powers of all of the harmonics then it follows that sum of all these high and low amplitudes might remain nearly constant--the amount of damping doesn't change instrument's overall loudness a lot. Since most of the power of a bowed string note comes from the first few harmonics then a note's power is largely determined where these harmonics fall on the instrument's frequency response curve (FRC). Higher damping smooths out the FRC so the instrument's notes are likely to be more even in loudness. Sometimes increased damping happens simultaneously with increased mass like what might happen with real thick layers of varnish. I suspect that the decrease in sound power is a result of more mass rather than more damping. It might be possible that a wood might change over time by micro cracking which could increase its damping without increasing its mass. The wood might also actually decrease in density. So a benefit would be increased loudness with better note evenness. It also might be possible with special treatment or aging to decrease both the wood's damping and its density which would make the instrument louder but the notes might become less even. All of this is just speculation on my part.
  4. Marty Kasprzyk

    Plate Thickness/Overall Weight

    The instrument weight concern might be a regional question. Just out of curiosity, what does a full shovel full of snow weigh where you are out in Utah? Back here in Western NY the forecast is for some heavy mush. Maybe the instruments follow snow g/cc.
  5. Marty Kasprzyk

    Ray Chen plays a modern violin on the latest recording?

    The performer might use the new one for the recordings and the road and just mention the Strad in the program book.
  6. Marty Kasprzyk

    Another extreme arching experiment

    Hi Don, Will Your bass bar follow along parallel to the inside surface corner kink?
  7. Marty Kasprzyk

    Question for makers who work alone

    Does the ticket buying audience seated far away care about purfling worksmanship? Who are we trying to please?
  8. Marty Kasprzyk

    Another extreme arching experiment

    Yes but the flat top allows the bridge to easily slide and west when you do impact hammer tests on the bridge or when you bow hard which screws up the sound. So one purpose of the curved cross arch is to keep the bridge from moving around. I make my tops flat and I avoid this problem by gluing the bridge onto the top. I used to be traditional and used hide glue but now I use Gorilla glue. They always sound better after the bridge is glued and the frequency response curves show a higher output of some resonance peaks. While I'm at it--I believe the reason why good bridge fitting is so important is that a large contact surface allows good vibration transfer between the bridge and the top plate. You don't want to have air gaps between the mating surfaces giving large impedance mismatches. Using glue, which has properties more similar to wood than air, ensures this doesn't happen. Don't try this at home.
  9. Marty Kasprzyk

    Carbon back - huge difference?

    I recommend making more of them.
  10. Marty Kasprzyk

    top only or whole body?

    Most of the low frequency sound comes out of the f holes and is monopole -meaning it goes off equally in all directions. The higher frequencies are however directional and its possible for a beam of sound going out and missing the player. It's there but the player doesn't hear it much. The question is: what directions do you want the high frequency sound to go? If it comes off the cello's back it is probably going into the player's body or bouncing off the floor, then hitting other players or the back of the hall and eventually, with only little left unabsorbed, getting to the audience. So it makes sense to limit the amount coming off the back. This is done by making it stiff and heavy so it doesn't vibrate much while the top is made light and flexible so it can radiate sound easily. The ribs also radiate high frequency sound but I suspect their main contribution is to provide body flexibility needed to produce volume changes necessary for air flow thru the f holes to produce low frequency sounds. Hence the ribs are made thin. It is my guess that this is the reason why the single piece back and rib construction made from a carved out block for medieval fiddles was abandoned as a construction method. The newer separate thin bent ribs made the instrument cavity easier to expand and contract to produce lower frequencies. This in turn made for a richer and more liked sound.
  11. Marty Kasprzyk

    'taptones' of a unstrung violin in the white

    If you want a bright sounding viola then you should hit it with a hard hammer. If you want a mellow sounding viola then you should hit it with a soft rubber faced hammer. If nothing sounds good just hit your viola really hard.
  12. Marty Kasprzyk

    "Dutch Violin"

    I too make my violins and violas with the bridge treble foot resting directly on a sound post that goes through a hole in the top like the ancient Crwth. I also glue every thing together-- the bridge to the sound post, and the sound post to the back. This arrangement has the advantage of eliminating endless bridge and sound post adjustments to fustrate those who never seem to be satisfied.
  13. Marty Kasprzyk

    thin back effect

    Can you use this stuff for the entire plate?
  14. Marty Kasprzyk

    thin back effect

    An old friend had a similar cheap violin which had great sentimental value. I made a large breast patch for the back to thicken it. It was a lot of work but it sounded much better and he was very appreciative. He's now deceased but I hope his violin lives on.
  15. Marty Kasprzyk

    slab cut - wide grain front

    Tops naturally come out made with the annual ringed closely perpendicular to the surfaces as a consequence of the wedge splitting and the length to width proportions of the violin were established long ago for the resulting longitudinal to cross grain elastic modulus ratio. If you wanted to keep the same sound character by keeping the same mode frequencies with off angle (45 degree example) low cross wise stiffness wood made by sawing it would be necessary to use narrower width bouts. While that might be able to work acoustically nobody would accept the skinny appearance hence it's not used. The opposite problem exists for plywood which has little stiffness difference in different directions. In this case the instruments should be made with wider proportions. But nobody likes a fat belly. Projection is important for violas too so you do want to have a long flight path.