Hypothetical Luthiery Question

Subject: Hypothetical Luthiery Question
From: Bee-dubya-ell
Date: 19 Nov 03 - 12:29 AM

This guitar belongs to a jazz guitarist friend of mine. It's a classical guitar/fretless bass hybrid, custom built by electric bass builder Rob Allen. It has the D through high E strings of a classical guitar plus the strings of a regular four-string bass guitar (fretless in this case) all on one neck. It has separate bass and treble bridges with transducers so that the two signals can be sent to separate amps. It is a remarkable instrument and my friend plays it remarkably well, playing the melody with his fingers on the four classical strings while playing bass lines with his thumb.

The hypothetical luthiery question that I have is, "Would it be possible to build an acoustic version of this instrument?" I'm thinking that it would be almost impossible. Maybe it could be done using steel strings for the treble side, but my friend is strictly a nylon string player. It would seem to me that for an acoustic bass you would need a large body with stiff bracing, but nylon strings would sound dead on such a body. And if you were to build lightly enough to make the nylon sound good, the bass strings would pull the thing apart.

One idea that came to mind (and I don't know how conceivable it really is) would be to build a twin-chambered guitar. Run a piece of wood down the middle of the body (similar to the way semi-hollow electrics like ES-335's are built, only not as massive) and thus divide it into a beefed-up chamber for the bass side and a more lightly braced chamber voiced for the nylon strings. Soundholes would have to be placed in an unconventional location but, hey, it would be a pretty unconventional instrument anyway.

Anybody got any ideas or input?

Bruce

Subject: RE: Hypothetical Luthiery Question
From: Cluin
Date: 19 Nov 03 - 12:48 AM

If Linda Manzer can build any of these machines. I'm sure she could tackle the one you suggest.

One I'd like to have would be an acoustic/electric 2 neck mandolin over guitar axe. It would save my having to switch back and forth and I could alternate easily within the song/tune. I do that now, but it takes a few seconds to reach for the mando and balance it on top of the guitar. Works when I'm playing with others, but not solo.

Subject: RE: Hypothetical Luthiery Question
From: mooman
Date: 19 Nov 03 - 04:53 AM

Theoretically it should be possible with some clever design of positioning of necks, bracing and top thickness. Possibly dual chamber, possibly single.

I was going to blicky Linda's site but Cluin beat me to it.

I'd be willing to try it for the right price!!! (;>)

Peace

moo

Subject: RE: Hypothetical Luthiery Question
From: smallpiper
Date: 19 Nov 03 - 05:03 AM

You can get Gell strings for the bass and they sound great and don't have to be under such tension as steel ones.

Subject: RE: Hypothetical Luthiery Question
From: Leadfingers
Date: 19 Nov 03 - 05:48 AM

The Corries were playing multi instruments way back then,with an assortment of necks on one body.Sorry I dont have any piccies.Just thought I'd mention it.

Subject: RE: Hypothetical Luthiery Question
From: Watson
Date: 19 Nov 03 - 07:44 AM

Pictures of the Corries' combolins here.

Subject: RE: Hypothetical Luthiery Question
From: Mooh
Date: 19 Nov 03 - 09:58 AM

Quite possible, but some allowances would need to be made.

I'd go with one sound box, large like a jumbo guitar but perhaps fitted with a wedge shape (a la Manzer) and rolled arm rest and waist (a la Laskin) to make it more comfortable.

A 12 fret neck with or without a cutaway, and light weight and mini tuning machines with wood buttons would improve the balance (see a Stewart MacDonald catalogue/website). The 12 fret neck would also move the bridge back to a wider part of the top plate, for perhaps some sonic advantage.

Though a fan fret system would improve the scale length for the lower strings, it might be too radical...I think I'd try it. Double truss like the old Guild 12 strings, or single truss and a laminate neck (my preference) and an ebony fretboard for the fretlessnesslike (to coin a term) feel.

Go with wood which would react well to the wide range of timbres (how's that for a double pun?) like koa, maple, or rosewood back and sides, and spruce for the top unless koa would make the top stiffer (ask your friendly neighbourhood luthier).

I don't think any radical bracing is in order, a typical X brace would work, though you might want to research the bracing on some of the available 8 to 11 string classical guitars which appear now and again.

I'd go with hard tension high strings for the classical portion of the instrument and lighter bass strings. I really like the nylon tape wound (over steel or stainless, from Fender and LaBella) bass strings for fretless and fretted bass. Check out one of the online string guage/scale length charts to sort out guages.

This ain't no cowboy geetar, is it!

Peace, Mooh.

Subject: RE: Hypothetical Luthiery Question
From: GUEST,Poppa Gator, cookieless at work
Date: 19 Nov 03 - 10:32 AM

Anyone interested in this thread should take a peek at Phil DeGruy's instrument:

http://www.guitarp.com/guitarp.html

Phil is an absolutely amazing player, and perhaps the craziest person free to walk the streets of New Orleans (which is saying something). If you have audio and/or video capabilities on your computer, check out the samples on his home page:

www.guitarp.com

Subject: RE: Hypothetical Luthiery Question
From: Bee-dubya-ell
Date: 19 Nov 03 - 11:07 AM

Nope. Cowboys wouldn't know what to do with such a thing. Hell, I won't even touch it and I'm far from a cowboy.

In case you're interested, here are some pictures of other guitars from the same guy's collection. Two are "conventional" 7-strings and two are 5 classical string/3 (fretted) bass string hybrids, one with fan frets. There's also a link to "under construction" pics of the previously mentioned Rob Allen instrument on the same page.

Yes, the boy's got some unique axes.

Thanks for the input, all.

Bruce

Subject: RE: Hypothetical Luthiery Question
From: Mooh
Date: 19 Nov 03 - 02:18 PM

Bruce...Cool stuff! Thanks for the diversion. Mooh.