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tangimango
10-15-2014, 08:25 PM
Aloha, if sound is mostly generated by the front soundboard and the back is to reflect the sound will a back being 3mm thick instead of a 2mm thick make any diffrrence?

Michael Smith
10-15-2014, 09:20 PM
Short answer is very little. It matters much more how dense the wood itself is. Rosewood very loud and bright, Redwood very soft and warm, other woods somewhere in-between.

Timbuck
10-15-2014, 09:31 PM
I restored an old island uke earlier this year and I removed the back, and measured it at about 1/8" .. it was a pretty loud sounding uke as well.
http://i219.photobucket.com/albums/cc143/shiregreenbod/mossback_zpsd49aa428.jpg (http://s219.photobucket.com/user/shiregreenbod/media/mossback_zpsd49aa428.jpg.html)

Michael N.
10-15-2014, 09:50 PM
Short answer is very little. It matters much more how dense the wood itself is. Rosewood very loud and bright, Redwood very soft and warm, other woods somewhere in-between.

I think that may well be another myth that gets banded about all the time. The only real way to tell is to position yourself in front of the Uke and compare instruments side by side, blindfold. I've done this kind of test many times and the results are frightening! Many of those pre conceived notions are done for. Of course the more that folk state that Rosewood sounds loud and bright the more that people will 'hear' loud and bright whenever they see a Rosewood instrument! We hear so much with our eyes.

tangimango
10-15-2014, 11:10 PM
Thanks, basically just adds a little more weight to the uke.

DennisK
10-16-2014, 12:04 AM
Kind of hard to play ukulele without damping it out against your chest anyway.

coolkayaker1
10-16-2014, 03:17 AM
would a uke require less back bracing, esp. cross bracing, if the backwood were thicker? if less stout bracing would be necessary, and if backwood thickness matters little for sound, why not make it thick enough to not require bracing, a cost savings (despite weight gain) esp on mass produced ukes. this is a question, i don't know

IamNoMan
10-16-2014, 03:26 AM
Kind of hard to play ukulele without damping it out against your chest anyway.
Around Galax VA they make deep bodied mountain dulcimers and frequently add a bottom sounding board spaced ~.25" from main body. These instruments are LOUD. Typically used for dances. The same principle might be considered for ukes and would keep the sound chamber away from the chest.

southcoastukes
10-16-2014, 08:36 AM
The question might be better phrased in terms of flexibility.

We've built both solid and the old style cypress lined backs. The latter, when using the same outer species as the solid backs, were stiffer. The more flexible backs produced a deeper resonance. For that matter, the same is true for flexibility throughout the entire soundbox.

In other words, tangi, you should get a bit deeper resonance if your thinner back is also braced in a way that allows it to be more flexible. That may or may not be good, depending on what you want to do with the design as a whole.

DennisK
10-16-2014, 01:16 PM
Around Galax VA they make deep bodied mountain dulcimers and frequently add a bottom sounding board spaced ~.25" from main body. These instruments are LOUD. Typically used for dances. The same principle might be considered for ukes and would keep the sound chamber away from the chest.
Yeah, that would be a good design for ukes. I've seen it done for guitars, but those are easy enough to play without damping out the actual back so I haven't tried it yet. I've only built one ukulele so far, but I do prefer the tone with the back undamped (concert size, ziricote back, about 1.7mm thick, 3 cross braces). More reverby.


would a uke require less back bracing, esp. cross bracing, if the backwood were thicker? if less stout bracing would be necessary, and if backwood thickness matters little for sound, why not make it thick enough to not require bracing, a cost savings (despite weight gain) esp on mass produced ukes. this is a question, i don't know
It would still be easier to crack from pressure/impacts than a back with cross bracing, but otherwise should be fine. Indeed kind of surprising it's not done more often.

Moore Bettah Ukuleles
10-16-2014, 01:35 PM
David Hurd used to tune his backs to comply with his tops to eliminate any dead notes or areas on the fret board. I've learned to tune my backs in much the same way so to me, yes, back thickness does matter.