X.brace in old Gibson A3

[Jan Ellefsen]

I have just started restoring a white 1923 Gibson A3, that has been in my loft for many years. When I got it, the back had fallen off and there are several open seems.
I suddenly got the idea that maybe it would be a good idea to install an x-brace instead of the small, original brace by the sound hole. Would it improve the sound, or should I leave it as it is?

[pops1]

I have a 60's Gibson A mandolin that has been converted to an X brace. It has ff holes instead of the oval hole you have, but I like the sound. The 60' weren't that great for Gibson mandolins anyway so no biggie. I got it that way so I wasn't plagued by the decision of altering the mandolin.

[Mike Buesseler]

I know at least one luthier (Don Paine@Pomeroy) who uses x-braces on his oval hole mandolins. He’s finishing one for me right now. It is the same design as early Gibson As, except for the braces.

[mrmando]

I think it would be an interesting project if you're up for it. I don't know exactly how it would affect the sound. A3s usually sound pretty good with the transverse brace, but this experiment might yield some insight.

[j. condino]

Structurally an X brace is stronger than a single transverse brace.

Tonally, it will still sound like an old oval hole mandolin, but have bit more complexity & overtones; slightly more modern sounding.

Do not overbuild it; make them light! Remember that adding height is cube the strength of adding width.

Socially, there will be plenty crusty crusty crusty half deaf old geezers who will gladly scream "Blasphemy! Whole lotta nuthin'..."

I've X braced about a dozen old Gibson A's & do it for all of my new build oval hole instruments.

[MikeEdgerton]

...Socially, there will be plenty crusty crusty crusty half deaf old geezers who will gladly scream "Blasphemy! Whole lotta nuthin'..."

Well, not this crusty crusty crusty half deaf old geezer. I like hot rods and hell, it's his instrument so he gets to make the rules.

[Sue Rieter]

Plus it already pretty much fell apart on it's own. Isn't that a sign of opportunity knocking?

[mrmando]

Tonally, it will still sound like an old oval hole mandolin, but have bit more complexity & overtones; slightly more modern sounding.

Would you say it's less "tubby" with X braces?

[Charles E.]

Would you say it's less "tubby" with X braces?

I would say "slightly pretentious but not too overbearing".

James, did you do any regraduations before installing the X-brace?

[peter.coombe]

What James said.

[rcc56]

When I bought my mandola over 35 years ago, it had to be opened up to repair a badly cracked tail block. The brace was falling out of there.

I was a beginner at repair work, and didn't have a shop in those days, so I paid a visit to Tom Morgan, and he suggested that I replace the brace with tone bars. He was kind enough to supply the spruce, lay off and cut the radius for me while I watched, and mark the position on the top where they needed to go.

I glued them in, then started carving. As a beginner, I may have carved them a little bit on the light side, but the instrument is still holding together. I do de-tune it a step when it goes in the case for a long period of time.

It sounds good enough that I played it on Norman Blake's record "Flower From the Fields of Alabama," also on the first Fletcher Bright Fiddle Band album; and Pete Ostroushko used it on one of his records.

If the top ever does start to sink while I'm still young enough to work on it, I'll open it back up and redo it. If it doesn't sink until 2040 or so, it will be someone else's problem.

[eightmoremiles]

Try putting a thin strip of carbon fiber between two thin pieces of wood in the braces. I had that done to a 70s F5 and it gave it a dramatic increase in volume, sharper attack and a much different tone.

[j. condino]

I would say "slightly pretentious but not too overbearing".

James, did you do any regraduations before installing the X-brace?

My favorite oval holed mandolins are the mid to late teens models; they tend to be thicker and have a bit more crispness, while the 20s era are already thinner and have...maybe a little bit more roundness and warmth. If you are already starting with a 1923, it would be easy to make it too thin. Mandolins are complex and it is easy to think that if 5 mm sounds good then 4 mm will be better and 3 mm will kick @$$...only to find out that all of your existing high end dropped out at 4.2mm. I tend to feel that transverse braced, short scale mahogany / Spanish cedar necked, oval holed mandolins have a different complexity than parallel braced, long maple necked F hole instruments.

Even though almost every Stradivari in existence has been re-graduated (and has nail holding the neck on!!!!!), I'm cautious of re-graduations done by folks who are not experts in the field. Graduations, arch style + height, and mass/ density / speed of sound (radiation ratio) all play important roles in the voicing of a top. Graduation changes are just one component, not a magic panacea.

Historic instruments are precious and few. I encourage everyone to get very creative with their personal new builds, but there are limits with old ones.

It was much more simple back when we all though "random hippee sanding" would cure everything....

[Jan Ellefsen]

Thanks for all the good advice. I will go for it and make some x-braces. I will keep you updated on the results.As you can see there is some work to be done, but no cracks anywhere except the side cracks by the tail block.

[Rob Roy]

I experimented with this. I got an old reject F4 top out of the Gibson basement when I was in the Kalamazoo area long ago. After reading about how the old single transverse brace was prone to coming loose with time, I decided to put the X brace in mine.

Tonewise, it's still very much an oval A with that rich, tubby tone. Compared to it's Gibson counterpart, I'd say the G string is a little less thumpy and there is definitely a lot of sustain (and volume!) in this box. full disclosure: I did use soft maple, flat grain for the back and rims instead of birch and a modern shape (F5 with the scroll and points lopped off).

[Vernon Hughes]

I did X bracing in an old very sunken top gibson project mandola years ago. With lots of humidification and time I managed to regain the arch and thought X bracing would help keep it supported. It worked out fine and held up nicely. Sounded just like it should have when it was completed, a nice round vintage gibson sound.