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Hi folks,
I have a question that I hope a few of you with experience in both tapered and scalloped styles can answer. I normally use scalloped but I want to try tapered. It seems to me that because of how much stiffer behind the bridge tapered bracing will be compared to scalloped, that the overall height of the x's at the intersection should be reduced somewhat.
Is this so?
And if so, by how much?
Thanks

It depends on the size of the body. On a 15" or wider lower bout, I don't go much below .6". If the tap tone is a little dead, I'll go down a bit more. .040" or so, but most material removal happens below the X & on the tone bars / finger braces.
On a little guitar, I'll take it down to around .5".
I experiment a little bit with every instrument & this is still very much a 'work in progress'.

Standard '000'...

You need to remember that none of this happens in a vacuum. Daniel says he doesn't go below .6" on a 15"+ guitar, but there is more to the question than that -- first and foremost is what radius is the top. A true flat top needs higher bracing than one with a 25' radius top. How stiff is your top? Are you using standard or lattice bracing -- all of these affect the determination of what you need to do in terms of bracing.

28' radius, standard pattern. I'm just thinking that since behind the bridge is stiffer, the bridge won't roll as much, so it might not need to be as strong in front of the bridge. But I think I'll just leave them normal height for now, work my way down, and see what happens as I go...

I'm certainly far from an expert on this but I built the stew-mac 000 kit which called for scalloped braces and straight rims (i.e. no real profile on the rims). I ended up profiling the rims to 25' and kept the braces tapered with the intent of scalloping them once the guitar was done to learn how that whole thing works.

Once I was done, I ended up liking the sound as-is that I never got around to scalloping them. I've received quite a few compliments from some experienced luthiers and players that this guit has a very good sound and was even asked what I did to "hot rod" the kit. I'm not saying it's a masterpiece or anything just that it's received some favorable compliments.

I basically left the braces at the height specified by the plan but triangulated them a bit. Here's a pic I found. The tone bars came pre-shaped and I decided to use them as is.

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You need to think about the guitar as a complete system. The fact that the braces behind the X are scalloped or not doesn't have anything to do with the strength of the upper arms of the X. It all needs to be balanced.

If the upper arms of the X are weak it will permit the area in front of the bridge to dive and it won't matter whether or not the lower arms of the X are stiff. You need to voice both the upper and lower arms of the X, regardless of whether lower arms are tapered and or scalloped.