Voicing method?

[ShaneJ]

A year or more ago, I saw something on the internet somewhere about voicing mandolins or maybe violins. #The luthier had a speaker in a box with a hole in the top. #He would lay an instrument top upside down on the hole and play a certain tone through the speaker. #He had metal filings or something dusted on the inside (bowl) of the top, and when the tone excited the plate the filings would bounce around and develop a pattern.

Seems like there was a name for this method of voicing a plate, but I can't remember what it was. #Anyone here of this or have experience with it? #Better than tap tuning? #Just different? #Thanks....

[Chris Baird]

Chladni patterns. #It is usefull for getting a visual of the various modes of a plate. #I just use a little guitar amp and a freeware tone generator, some foam to support the nodes, and some sand, sawdust, glitter, etc. Google Chladni.

[Stephen Perry]

EZ to make the patterns. More difficult to figure out what to do with them. Much argument over whether free plate modal analysis really has much to do with final instrument behavior.

[ShaneJ]

Thanks guys. I couldn't make much out of the info either. Don't think I'll go to the trouble of making a sound box, etc..

[John Bertotti]

Just out of curiosity we have discussed the different patterns but how relevant is the amplitude (in this case I mean volume) at which the patterns appear? Maybe this would give a better indication of the plate response. John

[Luthier Vandross]

Well, it 'could be'..

Best way is to beat the #### out of every instrument you build, and keep building. After a while, you can tell what they are screaming.



M

[Luthier Vandross]

Uhh... that word was not a real expletive..

M

[HoGo]

Search for Mike Nelson's page. I think that is where you saw the info. I must agree there is argument as to what the modes mean. I feel there is something the modes (with some other data) can tell about the mandolin, but no one knows for shure. Or at least, I don't know of any papers with substantial info about this.

[Dave Cohen]

There has been extensive discussion of free plate tuning in the violin world, and some in classical guitars as well. The main problem is that "free plate tuning" tunes the modes of the unattached plates, and those modes are completely different than the modes of the plates in the assembled instrument. In thet mid-90s, two builders working independently (Schleske and Atwood) attempted to follow the free plate modes into aassembled instruments, and found that they couldn't. However, that doesn't mean that there is no validity to free plate tuning, only that we don't really understand it. Thee are still advocates of free plate tuning, and they feel that they get good results from it.

[cal3g]

Not to sound like I am not in agreement with technology, but when some of the best mandolins ever built did they actually use the technology that we do today, most likely not. How did they do it, does anyone know, I have searched for the answer and can not find it. Personally I don't want to go to a bunch of expense to buy this gadget or that gadget, but would like to see if there is an older tried and tested true way to tune the Mandolin, how much wood to take off here and take off there to make at least a good sounding Mandolin.

Just IMHO

Regards
Garry Garcia

[Chris Baird]

It is my belief that as far as practical building goes that a builder given enough talent and experience can use a variety of subtle observations to voice an instrument at least as well as someone using scientific methods and devices. I think that if ones goal is to build better instrument it is best to stick to easier scientific observations and use the body's senses to fill in the rest. If it is your goal to understand fully what is going on and why then the full scientific way is best. I have some curiosity about why things are the way they are but mostly I just want to build better mandolins. So I tap, listen, flex, listen....

[John Bertotti]

We are walking organic computers with sensors arrays all over the place. The problem is most people haven't learned to pay attention to every detail and every sensory input. Start paying attention and taking notes. Then you'll be using a very complex computer and sensors and they're free! am I right? I think so but that doesn't mean I don't like gizmos. John

[Stephen Perry]

I've come to the conclusion that how I think determines how my instruments sound. They sound better all the time, but they always sound like mine. I've seen violins where mode 5 (ring mode) will blow glitter up 5 inches. These are loud instruments, but not necessarily the most even in response.

At least I don't have to worry about it. My laptop is kaput and that's what the frequency generator is on!

Spectral analysis programs offer some help, too. But I'm too impatient for them.

Steve

[PaulD]

My speculation is that gadgets and gizmos may help compensate for lack of experience for those of us that would like to build a decent instrument but can't immerse themselves like a full-time builder. They could certainly be used to supplement the senses for experienced builders, and they would add a repeatable, objective comparison between instruments. Ultimately I think repeat builders will probably tune to the sound they like whether they use their senses or try to optimize what they see using scientific methods.

To Garry's point; I'm going to invest in materials for when I can start building, rather than gadgets. I may set up a computer and a speaker to get some visuals for curiosity's sake because I've got the hardware lying around, but I also plan to rely on a local instrument builder's group so I can learn from their experience when voicing my first instruments. I intend to try to discipline myself to take notes, but I'm not a very discplined person when it comes to note taking or "journaling" (one of those '90s noun-into-verb words!). I also like the idea of the removable back as posted on MIMF and referenced here; that way I can play and experiment before I seal it up for good.

Paul Doubek