Violin Forum/Message Board

[Stradigenious]

Hy

I've seen a youtube video from Bill Sampson talking about the importance of tuning the back and plate to certain frequencies.

http://www.youtube.com/watch?v=nOMJDdRm1Hc&feature=related

What is still unclear to me is, whether the belly and the back should be tuned to the same frequencies or not?

Anybody here who knows something about that?

Thanks

Stradigenious
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www.spanishguitars.ch

[actonern]

From what I have read, plate tuning has pretty much been abandoned by top makers...

[violinarius]

[Dave Chandler]

If you're still on your first few violins, plate tuning is the least of your concerns. I've only made a dozen violins, but my observation is that there are four things you need to be absolutely on target, and plate tuning will take care of itself. They are:

1. Form shape -- balance, accuracy, and symetry
2. Arching -- within 1/10mm of original (this is my standard that I try to achieve, some probably do better than I but my calipers probably aren't any more accurate than this anyway) especially all along the long arch
3. Graduation -- again within 1/10mm of original, right up to the linings and blocks
4. Bass bar shape -- this you'll need to look through Michael Darnton's old posts, he'll give you a great starting point on heights along the bar measured through the belly.

If you can get these things on the money, they should be in the optimum range for plate tone -- at least the main modes.

I look at violin making as if I were a bell maker. A bell's sound is dependent on its absolute round shape at the bell opening (symetry), the correctness of its form (arching) from top to bottom, and the consistency of its thichness (graduation). Get these things right, and the bell (violin) should sing! (maybe it'll sing -- there are a lot of other things you can screw up too, that's why its an art, not a science).
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Dave in the Blue Ridge
Southern Violin Association

"Success is the ability to go from one failure to the next with no loss of enthusiasm" Winston Churchill

"I took the road less travelled, and now I don't know where I am." Marco Polo

[John Cadd]

Here`s the gist of what Sacconi writes about lots of Strad violins that he had a chance to study in detail. The separated plates were tuned to F.(above open D) top and back. Edit---( that`s with varnish already applied by Stradivarius )---- When assembled as a box and without soundpost the note was around Bb --top and back. The air resonance was also Bb (ish). That would be a full body and not a skinny one. The mode tuning site mentioned above is full of good info and I think it shows there is more than one way to make a violin. It may not contradict Sacconi . You will notice a different note in a violin plate depending where you hold it and where you tap it .The notes that Sacconi heard were knuckle taps around the bridge area and holding by the top edge (I think).
Also useful is the gauging tool I described in a tool topic. There is a rubber tyred wheel one side , a thickness adjuster , and a sharp blade to scratch the other side.

[sdantonio]

I had the opportunity to study under one of the founders of plate tuning. It is basically a way to visualize the tap tones. Plate tuning works with exactly the same tap tones you work with when you whack the instrument with your thumb, except, instead of judging everything by a ring tone you have a visible pattern and frequency numbers to back you up. Don't get me wrong, it is nor a substitute for tap tones. It is important to develop your ears too. It is just one more tool to use.

Plate tuning should never be "violin making by the numbers". Anyone who treats it as such doesn't really understand it. Like tap tones, plate patterns and frequencies are guideposts along the way. Not the goal in themselves.

Skewed patterns can help you to know that you have more stiffness on one side than the other. To high a frequency can suggest that you may want to do some thinning.

Fundamentally though, the wood is what the wood is. Plate tuning is not some magical formula to turn a crap piece of wood into a Strad (wish it were that simple). But in the right hands, it can be a good tool in perfecting your craft.

All the people I know who pioneered it (or the top makers who used it) that I know are still using it. As with anything that is artistic though, the more you know about plate tuning, the more you begin to say things like "there is definitely more here going on than we understand... but were learning".

Platetuning.org on first glance implies that there are hard fast numbers to shoot for. Read between the lines and they admit that these are just guideposts along the way to making a good instrument. N Harris pioneered the combination of frequencies, modes and plate masses combined. I've heard lots of problems with blindly shooting for these numbers (especially trying to hit this combination perfectly).

Traditional tap tones tells you that the tones should come in around a certain note and there should be an octave relation between two of the tones (x mode and o mode to use that plate tuning terminology). Plate tuning just gives you numbers and pictures that can either help you or confuse you more.

Steven

[Oded Kishony]

[sdantonio]

I spent about 5 years studying with Al Carruth who worked on a lot of the fundamentals with Carleen Hutchins (plate shape and arching height effects on mode shapes to mention only one of the projects). While I was studying with him I remember he would get quite a few research assignments from Carleen. Thinking back on it, he got a taste of what I went through in grad school javascript:emoticon(''). He is still quite active on fundamental research on wood properties if you watch his posts on left-brain lutherie

Granted, this isn't as old as Herron-Allen mention of plate tuning in his late 1880's book. But then, he did it by rubbing a bow against the edge of the plate.

[Oded Kishony]

I know Al Carruth, very bright guy with solid ideas, even if I don't always agree with him. Started out on guitars IIRC.


Oded

[sdantonio]

He still does a lot of guitars. Almost got Sharon Isbin to pick one up, but she had just bought a new one a few months earlier and couldn't justify the second purchase.

He is a good guy, excellent teacher too. Lots of patience for people like me