Peter K-G

http://www.thestradsound.com/varnish/varnish-recipe-16-06-2018 https://photos.google.com/share/AF1QipN3Jpu-WdwQgG14G2wNehnzu5c-XynpWpa7OX_K4jNzStyl6hqGGlMxkMJwXZ2ZBQ?key=MTNRdEs5ZGU0Q0gtVnNKLV9CQVhjM0h2dUJyWWF3

From the CT scan and graduation scheme there are a sound post patch and a larger breast patch

Just some more edge images

... but it's probably something more mysterious

Dirty old wood, might look like that

IT IS NOT THE VIOLIN WE SEE, IT'S THE RECORDING EQUIPMENT

=> DIFFERENT DEVICES/MIC => SAME VIOLIN/PLAYING IN ALL SPECTRUM PLOTS

Third device (Ipad 2018 better mic and sound) same violin and playing

Robert, I have done a lot of these analysis and if I miss your point, I think you are missing mine too. The most prominent factor that affects the spectrum is the recording device/mic! It is not possible to interpret spectrums taken by others to get any useful information about the violin. The only useful information is when you compare for your self several violins taken with the same equipment. This is one of the previous compared to using the same device but not so strong bowing and from about 2 m. What I can see is that it is taken with the same device.

Sure, my point stands though

Same violin, two different devices. G-String played at about the same distance to mics (both internal mics). My point would be that there is more difference in which device is used, than if played different violins recorded on the same device!

I don't think you should look at these analyzes as "facts" of what's going on. They are just helpful illustrations on what parts moves most on certain body frequencies.

There is not a big concave shape, but on this particular back the longitudinal arch is long and low and have CC like cross arch shapes. The phone camera lens lies somewhat too in the image. I also get different STLs depending on how i point to the middle or a rectangle in the middle I think it's pointless to record an open G-string playing with nothing to compare with. First it sound terrible and I get different sound/spectrum depending on which device I use. I have several PC/devices and it's very obvious that the device/mic setup stands for most of what the spectrum shows. Ipads are the most reliable of "cheap" analyzing equipment.

Powerful violin with low arch height and light plates (67 g/98 g) that are quite thick in relation to their density

With my basic structural engineering education and "sunt bondförnuft" the flat top will colapse inwards because suronding structure is stretched and bent. On a violin in really really complexed ways that are individual to every particular violin. But of cource there are some common prominant bending stretching in general on a violin because of its shape. I don't see that you have a question, because you allready know all this, read your web site many times. Over and out :)