Adapting patterns

[PiALaModem]

A customer asked me about having a soundhole on a mountain dulcimer in the shape of a deer or moose. That sounded fine, but when I started poking at the idea with a sharp stick, I realized that just a hole in the shape of a deer silhouette would lose a lot of detail. I wanted to be able to get the detail in, but then where would the outline come from? It can't be too fragile, as this is a musical instrument to be strummed.

I came across a pattern book called North Amwerican Wildlife Patterns by Lora Irish (published by guess who?), which contained patterns intended to be standalone outlines with internal details. I took one of these patterns, spray-glued it to a small piece of 1/8-inch walnut, which I then spray-glued to a piece of 1/8-inch butternut. I bevel-cut the outline at nine degrees so that the walnut dropped down into the the butternut, glued the walnut shape into the butternut hole, and then cut the internal details with the blade square to the table.

The result is below, if I managed to get it attached correctly. I used a scrap piece of butternut for this demo; the soundboard of the dulcimer will be of a similar piece.

[jttheclockman]

Steve

Looks good. I just love this artform and the things people think of. There is no better.

[GrayBeard Phil]

Oh well, there goes the last of my knowledge of Guitars down the drain.

{BTW, that looks very good, and very nice design with the contrasting wood}

For many years I thought that the sound hole was some sort of compromise between sound quality and volume and the mechanical compression forces on the wood caused by the strings. The stings are applying a large force to move the wood near the string attachment block up to the neck. Sound holes like yours I had thought would turn the top to splinters.

But I must be wrong.

Please post the finished dulcimer.

Phil

[PiALaModem]

Sound holes

Phil, hang onto that guitar knowledge. On a dulcimer, you have the fretboard attached all along the length of the soundboard (sometimes only at a sequence of points), while with a guitar, the soundhole sits in the open space of the soundboard between the bridge and the end of the fingerboard, where there is a lot of stress from the pull of the strings. The dulcimer fretboard takes pretty much the whole stress of the strings. This makes the shape, size, and location of the soundhole on a guitar much more important in terms of structure than it is on a dulcimer.

Musically, as opposed to structurally, the big thing about sound holes is their area. The proportion of the area of the opening(s) to the volume of the resonating chamber helps determine the main resonant frequency of the soundbox or resonator.

How soundholes are shaped may have some bearing on how the overtones are distributed, but this is theory that is just barely beginning to be explored. There is an idea about that the f-shaped holes on a violin, for example, help to break up the soundboard into different areas that resonate to different notes. This is different from the resonance of the soundbox, by the way. It's all really complicated and design consists of trying things and seeing if they work (within limits). I'm not going to even begin to get into bracing.

My avatar shows one of the wildest soundhole designs I've tried. This instrument has a decidedly smaller sound than another one I made of similar materials with more conventional soundholes. However, the character of the sound is also different, crisper and a little more distinct. Fortunately there is not one ideal dulcimer sound that a maker strives for every time (for most makers), and different instruments are better for different kinds of playing. That's how we get to sell more dulcimers -- here's one for fingerpicking, here's one for strumming, heh, heh, heh.

[CanadianScroller]

Kudos

Nice job on the soundhole!
I love it when people combine arts and skills together to come up with something unique.

[Neal Moore]

Steve...Willie Nelson has an old accoustic flat top on which he has worn a large hole through the finger board and top of the guitar. I think that instrument produces some of the most unique and pleasing sounds I've heard. One of those "happy accidents" that would be hard to engineer into the original instrument. Wish mine sounded like that but I'm not going to Whack an extra hole in it!!! Ha!! Ha!!

[GrayBeard Phil]

Steve:

Thanks for the clarificaton.

Phil.