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Just curious if there's a consensus on the difference in sound with let's say a guitar braced at 100 degree bracing vs. one with 95 or 90 degree.

Seems to my ears that the guitars with the wider x bracing have a significantly more bass/low mids oriented tone vs. the narrower bracing producing a slightly more high mids voice.

I'm asking because I've been getting quite a few more Gibson acoustics in my shop that have wide X bracing patterns and they seem to be very consistent in their tone. Martin has a few models with wider bracing and they also seem more prone to this bigger/bassier sound.

Any thoughts?

That's what I thought... not sure what you are experiencing with the difference in brands.

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

For the mass narrow angled bracing results in more stiffness in the longitudinal direction. A stiffer top will support higher notes better.

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http://www.Harvestmoonguitars.com

Your observations are right in line with what I'd expect to hear. Generally, the narrower layout would boost the treble end of the spectrum by allowing more lateral movement across the centerline of the top, where the bridge is more free to move side to side, while the wider layout would boost movement along the length of the body, where the bridge is more free to rock forward and back.

These trends seem play out when you compare steel string and classical bracing layouts. Steel strings are strong in the trebles compared to the nylon string family, so their bracing is more conducive to enhancing lower frequencies by allowing the bridge more freedom in the front to back rocking direction. Nylon and other non-steel strings as used in classicals are weaker in the treble end of the spectrum and don't need help in the bass, so most bracing in those guitars provide more freedom for the bridge to move side to side to bring up the trebles.

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formerly known around here as burbank
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http://www.patfosterguitars.com

I've noticed the same thing regarding Bass/Treble response with x-brace angle. To me, it seems that the angle of the X is one of the main factors in the overall sound you are going to get from the box.

For the past ten years or so I have been going with 102 degrees on my OM and SJ sized boxes and 96 degrees on my Jumbo sized box.

I felt the smaller bodies need some bass help hence the more open X and the Jumbo's needed to be held a little tighter to avoid boominess. Of course the location you put the X also determines Bass/Treble in the same manned, (forward shifting for a looser lower bout, etc.)

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Joe Beaver
Maker of Sawdust

I think the included angle of the 'x' brace is part of the situation, but not a determinant. I'd built two guitars with relatively wide (about 100 degrees) x-brace angles and just finished a third with more-or-less 90 degrees. All three were made in the same mold, the first two as 14-fretters, the third as a 12-fret neck on a 14-fret body. Thicknesses vary, the third being the deepest of the 3. The third is vastly stronger in bass than the first two. How the top is tuned and how the top braces are tuned seem to me to be stronger influencers of response. I'm also going to guess that where on the 'x' the bridge sits has an effect, too.

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Peter Havriluk

No doubt you had to reduce the X angle on your third instrument so that the bridge corners would still be located over the brace. Just moving that bridge deeper into the lower bout will have had a significant impact on tone — a well-known characteristic of 12 fretters and why they often exceed expectations. Builders often build 14-fret bodies with 13 frets to the body, just to capture that favorable shift in bridge location. Your third is quite a different beast next to your 14-fret instruments.


Sent from my iPad using Tapatalk

Tim, you sure got that right. I built the 12/14 to see what it would sound like, and as you said, it sure is different. Strange coincidence you mentioned, I three days ago I roughed out a 13-fret-at-the-body neck for my next project. Same body shadow, a quarter-inch thinner.

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Peter Havriluk

I’m on a 13 fret kick right now.