is there any change in sound quality between a curly koa or curly mahogny neck? or is it mostly cosmetic? seems most ukes are done with mahogny necks..thxs
There should be no problem using Koa as long as the neck to body joint is solid and the neck has some graphite truss rod added as reinforcement. The sound quality would be negligible between the two woods. Thousands of vintage ukes have Koa necks.
I think I actually prefer a nice curly koa neck for it's sound, but it is a lot more work and a lot more expensive.
A koa neck is not necessarily better, just different.
Personally I would never use a curly koa neck, I wouldn't trust it's strength or stability. The grain is just too short and radical. Maybe adding TWO stabilizing rods would make me feel more comfortable. The extra weight would throw the balance of my ukes out of whack as well.