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Hi, all--

I'm thinking of x-bracing the back of my current project (a small-bodied, mahogany steel string: 14" lower bout, but nearly full dreadnaught depth). This will be new for me--I've always used ladder bracing in the back.

All other data points being fairly consistent, has anyone had the opportunity to compare a given design with ladder- and x-braced backs?

I'd expect the x-braced back to be stiffer, but I'm curious to see what impact that will have on the finished instrument: more responsiveness? better bass? better balance?

Thanks in advance, and I'll post pictures as the project progresses.

-Kevin

I've used both styles: I did X-bracing for years, and am now going back more to ladder. All I can say is they're a _little_ different.

I started using X bracing in the hope that I could tune the free backs along with the tops and get them to match up better. Given the variability of back wood, and the differences from top wood in general, it didn't work out as I had thought it might. In the end, it turns out to be just about as easy and productive to tune ladder braced backs as X braced ones.

I will say that Fred Dickens used a rectangular brace system on backs: two across and two up and down. This allowed him to tune the 'ring' mode on backs, and get it to work with the top. One of the students is trying that out now, having thought of it independantly. We'll see how it works.

The 'cross dipole' mode on ladder braced backs is usally higher in pitch than it is on X braced ones. X braced backs can also have an 'extra' ring mode when assembled that will 'breath'; pump air through the hole, and this can effect the sound. Which is 'better' is an open question.