Official Luthiers Forum!

So with the great advice I recieved from the previous thread about a first build I have decided to shift gears a bit.

Looking around at tools, there are more tools (templates/molds etc...) readily available for an SJ200 style body shape than there are for an AJ shape. I like the SJ shape and I also love maple from working on violins so I thought why not? Plus maple is easy (cheap) to get and seems to be alot nicer to various stains and colors. The only downside I see to this body shape is that kits are not readily available for them.

What I'd like to do however is get some input on the bracing/construction for these bad boys. Alot of the modern 200s I have spent time with all seemed a bit "tight" and dense sounding (I have not played an older one yet). Even on a first guitar I'd like to avoid this and maybe shoot for a lighter built top, but I don't know how to do this.

I'm partially drawn to the idea of a 17" jumbo because with larger guitars you can mess things up a bit and then just pawn it off as "it's a strummer".

Has anyone built any 17" jumbos and what advice can you offer me on building them?

Literally I'm open to anything you want to share.

I've built and am building 3 17" jumbos. Two are based on a Washburn "Prairie State" that I made a mold for from luthiercooltools instructions that included 15' and 28' radius dishes. Got the bracing scheme off the Washburn using the inside/outside magnet trick for a template pattern. (Sorry Haans, not very Larson traditional). One is EIR/Sitka and almost finished with a Maple/Sitka.

The other is a J200 shape using the LMII plan drawn by Rick Micheletti.

The Prairie State Does not have a boomy bass and is fairly balanced across its range. Not sure what you mean by "tight".

Here's a pic... Was gonna call it "Mae West" for the big bottom, narrow waist. I like the slope shoulders.

Well Carl, I was surprised to find that Washburn (modern) had attempted a "Prairie State". I had built two 17" red spruce/maple and 4-5 16" with the short 22" scale. They all sounded VG but I preferred the 16" because of the very short scale and big sound. None of mine had whatever bracing Larsons used on the PS. Instead, I used a combination of X bracing and ladder bracing with laminated braces. The all sounded just fine and quite even. Here's a few photos. Never did get a full shot of the 17" but some of the construction photos are still around...











And a couple of 16"



I'd say unless you have plenty of bucks for custom cases. stick to a standard size jumbo...

"Mae West" is a nice looking guitar. I'm thinking just to stick to a standard template for my first one, nothing crazy and nothing special. If it's lame then that's the way it is, you learn best by embracing the suck. The prairie states are great guitars.

What I mean by "tight" is that they sound stiff, not much mid range with a bit of bass and alot of treble. Nothing wrong with that per-se but it just seems to my ears to be a bit tight sounding. Does that make sense?



Thanks for sharing those photos Haans, if anything on this forum I'd consider you the "jumbo king" seems like you've just made alot of them.

As far as cases go, there are cheap hard cases that fit a 17.5 lower bout, maybe not perfect but they'll fit.

Haans, I've been meaning to ask you, is that carbon fiber in your braces? Looks like maybe .045 in the X and maybe .022 in the others?

Or something else perhaps?

_________________
Joe Beaver
Maker of Sawdust

Nope, they are either BRW or Wenge. Never liked to use anything but wood in acoustic parts.
Thanks Dan, I did make a number of 16", but never thought of them as "Jumbos". I thought them to be more of a real guitar compared to the tiny taylor toy. I called them mini-jumbos. Charlie Hoffman called them the "perfect old man's guitar".

I agree with the concept. In my mind a "jumbo" was always a 17" or larger guitar.

I did find a sound clip of what I'd like to try to shoot for, Molly Tuttle on a J200. To my ears I just really like the big tone of this particular one. Haans if I played one of yours I'm certain that I'd enjoy hearing it over the regular J200, sadly there are none around me that I know about.



For the first one I'm likely just going to keep it stupid simple. Standard J200 shape, Single line binding, no binding on the fingerboard. What I'd like to work very hard on is the bracing/voicing etc... So any thoughts on a bracing pattern? Layout? Just brainstorming here guys. Haans any thoughts on bracing for a first attempt at a jumbo?

Dan, I have no idea. I do know that I used 3 tone bars on the 17", and laminated bracing on the X. That just might give you a cleaner sound without sacrificing the "large sound".

That's why I mentioned the LMII plan. I'm sure the bracing pattern is the same as the one in the sound sample.

Looks Marvin/Gilson to me...