Side profiles

[Dave Bagwill]

I was watching Doug Young playing a "boutique" small-bodied instrument, and noticed that the upper bout was as deep as the lower bout.

I do know the theories of side profiles, but still: there it was, a $5k instrument, apparently flaunting the rules.

So, making an OM or 00 sized instrument, why not use , say, a 3 7/8" height for both headblock and tailblock?

Another question: some of us use a 40' radius for the top, and do not profile the rim at the top, because at 40' the top does not need radiused kerfing.

So, with a flat rim on the bottom, we could by that logic use a 40' radius back and not have to radius the kerfing. So it would not be a strictly 'flat' back.

Thoughts? Stop me before I try it!!

[John Parchem]

I make some ukuleles that way. For guitars I like the look of a heel side smaller by about 5 mm than the tail. But there is no reason you can not do as you describe. Make sure for what ever depth you use it can still fit in an off the shelf case if that is important. The top side of the guitar has 6 - 7 mm of fretboard.

[Herman]

I know Bogdanovic makes classical guitars with the same height of the neck and tail block.
Herman

I have a lot of building books, but none of them tells about "side profile theory".
Dave, please enlighten me, or tell where to find.

[K Wiebusch]

Following this.

[Dave Bagwill]

No big 'theory' - wrong word, I guess, all I meant to say was that like all of you, I know the reasons for why the sides have a non-rectangular profile - mainly aesthetic - and that given a particular choice of body shape, say an OM, and choice of body depth, say 4" tailblock and 3 1/2" headblock, and choice of back radius, say 15' - then we know how to get the profile of the sides.

So nothing new, sorry if I made it sound like there is deep theory here - it's just practical carpentry basically.

[Herman]

Well, I have a little theory.

In loadspeakers they make "baffles" to avoid parallel boards and therefore fighting "standing" waves. What could cause wolf notes as the soundbox has specific space and a specific liking for one note. (Still my theory). And as "baffling" causes "confusion", no specific (wolf) note can rise above the rest.
All notes can be equally in the spectrum. An that is what we like in a loadspeaker and in an instrument.

By slanting the guitar body, next to doming, a form of baffling is achieved. Well, IMO.
Herman

[Dave Bagwill]

You could be right, Herman. That's interesting.