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About ctanzio

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    Philadelphia, PA USA

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  1. The two effects, showcasing the wood and a smooth finish, do not have to be mutually exclusive. Varnish layers of high clarity and carefully selected indexes of refraction can highlight grain structure and natural wood color variation in a spectacular way. If by "showcases the wood" you mean highlight a corduroy effect of differing winter and summer grain heights and various oversized pore structures, I would suggest that these types of effects require a type of "unnatural" processing of the wood, either by scrapping, sanding or grain raising, to achieve. So it is not like one method is p
  2. To get a uniform sheen, glossy, satin or whatever, you have two basic approaches: 1. Make sure the surface is "flat", i.e., no high/low spots. For this with sanding between varnish layers, you have to apply a sufficient varnish thickness so that when you sand, the entire surface will eventually become uniformly "flat" and the sheen from the sanding becomes consistent sheen everywhere. For your violin top, your surface has high/low spots and that causes the inconsistent sheen. If you try to make a surface "flat" by successive applications and sanding of colored varnish, it typically r
  3. 400 years after Francis Bacon formalized the Scientific Method, and people still cannot utter the simple phrase, "I do not know." Or maybe I missed the Psychic Powers class during my misspent college years? >gd&r<
  4. You might have failed to select a recording device. On the toolbar that runs across the top of the screen, locate the image of a microphone with a sliding scaled next to it that starts with a "-" and ends with a "+". Below that is a series of drop down menus. You should see a drop down next to another image of a microphone. Make sure something is selected there. Just to the left of those drop downs you will see scales that look like dB meters. There should be wording in one of the meters that says, "Click to Start Monitoring". Click that and the meters should start monitoring the dB level
  5. Could be just about anything. Modern nitrocellulose lacquers can be spray painted to a smooth, high gloss finish. Modern water-based polyurethanes can give spectacularly clear and smooth finishes that are impossible to visually distinguish from fine oil or spirit varnishes. French Polish is not a "varnish", but rather a method for applying spirit varnish, typically shellac. That can also give the finish that appears on your violin, but it is rather labor intensive to apply as the main varnish. It is commonly done as a finish step to apply a very thin, protective coat and add a bit of she
  6. If you enjoy playing it, avoid the urge to "fix" the varnish. You will have to apply a paint-like varnish over the existing varnish to get some sort of uniform color which can affect the tone, or remove the existing by a combination of chemical stripping, sanding and scarping which can affect the tone. A good cleaning (do a search for recommended methods), followed by a light polishing/coloring with a diluted amber shellac solution can place a gentle sheen and darken some of the lighter colored scratches without affecting the violin's playing characteristics. Again, do a little research o
  7. You can buy small cans of commercial shellac with a variety of natural colors. Dilute it 25% to 50% by volume with ethanol and let it stand in a capped bottle for a few days. The wax will settle to the lower half and leave a highly transparent, wax free shellac in the upper half than can be scooped out. A lot of the content of the can will go to waste, but you will get enough dewaxed shellac to varnish a lot of instruments. There are a variety of alcohol based dyes, like transtint, that do a great job shading shellac with just drop. The challenge is in the application. Since success
  8. Even if it resulted in a violin that was ugly, difficult to play in higher positions and awkward to hold on the shoulder? The point was that there are constraints on violin geometry and available wood properties unrelated to mode frequencies, as well as on the motivation of a maker to frequently redesign molds. In light of these constraints, wouldn't it be nice if a scientific study gave some quantitative insight on how to adjust violin performance by scraping the inside of the plate?
  9. Congratulations. I hope your new venture goes well. More pictures, please, of your work. They are so lovely.
  10. Not what I actually said, but even if I grant your selective editing of my post, unfortunately I do not understand your following comment.
  11. If one starts with a set of mode frequencies one wishes to obtain, then certainly a mold, arching shape and plate thickness plan can all be newly designed to achieve the desired results by applying the results of your study. Unfortunately, one typically starts with a mold and arching shape based on other factors, like visual effect or a desire to match a classic violin shape. Material properties are only somewhat under the control of the maker. That leaves plate thickness as the primary tool for adjusting the violin plate. So any quantifiable insight your study can give on where to a
  12. The additional reference was helpful. You published something in that second reference that might of interest to makers in general, and plate tuners specifically. To summarize for readers: for any given "reasonable" geometry change (the instrument still looks like a violin), it is possible to adjust the plate thickness to recover the mode frequencies of the original geometry. Another way of stating it might be that if a maker has a set of mode frequencies that make a "good" violin, then if they decide to change something about the geometry, they should be able to tune the plate to th
  13. It was an interesting read. Thanks for sharing. I do have some questions about the relevance of this study to actual violin making, but perhaps that is a topic that needs to be addressed by a further study. Here are some observations you might consider... In the simpler forms, neural nets are linear predictors of behavior. Inputs are multiplied by weighting factors (linear coefficients), and then the differences between the predictions and the observed results ("errors") are used to adjust ("train") the weighting factors. If you are varying the inputs of your experiments by "small" a
  14. Intonation so much improved from your last posting. You are adding that little "space" between detached notes that makes the melody stand out. It was a pleasure to listen too. Tempo still seems to be a challenge. Have you tried using a metronome? You can get free apps for your phone that work well. Each phrase in Annie's Song lands on an extended note that can challenge one's patience to stay with it for the full count, or to insert a proper amount of space to maintain a consistent rhythm. An added complication is that it is one of those songs that can benefit from a little lyrical f
  15. This might be a question for your tax accountant.