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It's a question aimed at those who switched to laminating their sides (or using tall solid linings).
I assume the added thickness, and/or mass, will raise the pitch of the rim.
Am I right to assume that this in turn will raise the pitch of the soundbox?

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Laurent,

I have been using 2 laminations at .04 with the lightest mahogany I can find as the inner layer. I don't think they are heavier than a single side of a dense rosewood. If they are, it is a very small bit. As for raising the pitch of the box, I didn't think the sides played a part in this assuming they are relatively stiff. If I am wrong here I would love to know. As an aside, I would think the stiffness would affect the pitch more as it affected the loss of energy in the top and back and I don't find double sides much stiffer than a single of the same thickness carefully bent. Maybe a little, but not much. The solid linings do make a huge difference though in that regard.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Burton, I think others who laminate their sides arrive at around .100" thickness, perhaps more. From what Howard and others say, the rim is extra-stiff and doesn't even need the mold at that point.
I'm just assuming the rim rings higher. Thus the soundbox when closed, maybe I am wrong, but it would seem logical. I'm wondering if you guys compensate for that in tuning the plates, opening a soundport etc.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I'm now using a solid tall lining inside a conventional thickness side set (about .085") for a total of around .170". Then I use reverse kerfing inside that...and top that off with a layer of carbon fiber...and then use three layers of .021" CF as binding on some guitars. These suckers are stiff...

I don't think the pitch of the sides has much to do with the tonal results which I think has more to do with how I graduate and brace the top. My back pitch is pretty high as that's got CF topped braces. With this series of guitars, I'm going for a lot of forward directional output and very solid mids without the muddy low end that can be captivating but ultimately not musically rewarding.

I have never thought of sides in terms of their pitch but rather their stiffness or floppiness.

I think with stiff sides you will get a lot of "ping" or what Rick calls forward movement. My opinion is that you gain this "ping" at the expense of some "warmth" - as in banjo like, or maybe piano like.

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Ken

Rick, I definitely notice an improvement in clarity and projection with a stiffer back and I tend to like it. Stiff sides probably contribute some more toward that goal, no doubt. Beyond structural integrity.
But I suspect the sides play a role, maybe very slight, in how the soundbox vibrates. Hence my query about the rim's pitch, or resonance, or whatever.
Ken, I agree: some of the "openness" (for lack of a better term…) of some vintage guitars may be because of extremely thin sides. Perhaps it transpires some sound toward the player, and/or absorbs energy, I am not sure.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/