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8 string bass conversion

this has probably been covered, but i couldn't find it in a search.

is there any way you could convert a 4 string to an 8? im talking more about the bridge here (obviously the second set of tuners would either fit or not fit depending on the headstock). where can you get 8 string hardware?

and for anyone who plays 8 string, what tuning works best for fingerstyle? i mean (Ee Aa Dd Gg) or (eE aA dD gG). thanks.
 
I couldn't tell you whether this will work, but Warmoth has this bridge:

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ABM makes one, too, I think. Check allparts.com. You could mount the second set of tuners at the bridge end. That might require some routing of the body.
 
The tension would be quite a bit higher, I'd think... also, if it's a Fender neck, I would think that it might be a bit cramped.

Warmoth 8-string necks are 1.75" wide at the nut. According to the Warmoth site, Fender jazz bass necks are 1.5" wide, and P-bass necks are 1.6875" wide.
 
Head on over to www.12stringbass.net and have a look in the Tech section. There are articles in there on a 5 string to 12 string conversion, and a 4 string to 11 string. You could probably apply that info to a 4 to 8 conversion.

hmm so if he could make a 5 into a 12 without the bass snapping, 4 to 8 doesnt seem like it would be too much of a problem.

so for the octave strings, do you use regular guitar machines?

and what are those strings anyways? are they just a regular set of piccolo's?
 
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:hiding:

(Function over form here.)
 
hmm so if he could make a 5 into a 12 without the bass snapping, 4 to 8 doesnt seem like it would be too much of a problem.

so for the octave strings, do you use regular guitar machines?

and what are those strings anyways? are they just a regular set of piccolo's?

I think he did tune down to D out of concern for tension on the neck, but I would think it would be less of an issue on an 8. My Dean 12 has dual trussrods, presumably for this reason.

On every production 8/12 string bass I've seen, the octave strings use guitar tuners. I usually buy 12 string sets, but I would have to assume that the octave strings are the same gauges as what would be found in a piccolo set.
 
The truss rods don't make the neck stronger- they just allow for more adjustment.

My Tobias is an 8 made from a 4 string, and there is plenty of adjustment left in the truss if it were to become a 12 (which wouldn't fit).

It's not like Dean 12 string necks are so much stronger than their 5 string necks- they're just slightly wider.
 
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Once upon a time, this was a '74 P-bass.

8string.jpg


Originally I spliced on a new headstock on the Fender maple neck. Warmoth hadn't come out with their 8-string neck yet, but Ken had sent me a drawing of the headstock to look at. (this was before email and stuff... ) My new head looked like a Flying V head.

Originally this looked like a Fender body, but then I cut the body to this shape back in 1980. At first it had a Badass II bridge, with four holes drilled through the body for the octave strings. Later I got one of the Schaller 8-string bridges when they came out.

The Fender neck held up fine with the extra strings, but it was a lousy neck, and didn't sound that great, so I made a new neck. The new neck is one fret shorter than a 34" scale... so it's about 32.5 I think. This wasn't necessary tough.
 
wow...a pbass?

this should have its own thread.

I don't think I have enough for a new thread, because unfortunately I don't have any photos of it's construction, except when I made the new neck, which also required inlaying a maple block to rout a new neck pocket.

I have a few photos of the new neck being made.

The history of the bass is a long one. It started off as something the singer in my band at the time got from a local guitar maker. He had moved the split pickup to the bridge position (where is still is) and made his own humbucker, which was installed at the neck position, but closer than the P pickup. It had a thin white single ply pickguard that extended up to the repositioned P at the bridge, kind of the way it is now, but different. It was sunburst with a maple fingerboard.

The fingerboard was in bad shape, and a lot of the frets were lose. It also needed to be planed flat.

I ended up with the bass (I traded her a Gibson EB-2 I wasn't using... wish I had that bass now) and removed the homemade humbucker, and put two DiMarzio Model P's in the bass. The was the late 70's, so those had just come out. I made a new pickguard out of black acrylic, and had series/parallel for each pickup, as well as phase and series for both pickups. I removed the sunburst and left it natural alder, and installed a Badass II. I also cut the headstock to look like a Music Man.

It was a cool bass, but the frets were still a mess.

Since it wasn't my main bass (I was playing a '74 Ric 4001) I decided to make it into an 8 string. I cut parts of the original headstock off, and spliced on a new piece of hard maple, using an odd joint I made up. It seemed to hold up well enough. :) I made a new brass nut for the bass, and added a metal bar to hold the strings down.

I got 4 Schaller mini bass machines, and 4 Gotoh guitar machines. I drilled four holes through the Badass all the way through the body, and installed ferrules in the back for the octave strings.

I wasn't confident about doing the fretwork myself, since it was such a mess, so I took it to a local repair shop, and explained the frets needed to be removed, and the board had to be planed down and new slots cut.

I got the bass back worst then it went in! The guy went on and on about how the fret slots were shot... totally ignoring the fact that I told him it needed to be planed and reslotted!

That was the last time anyone ever did any work on one of my basses. So he did me a favor since I learned to do the work myself!

In 1980 I cut the body to the shape you see, and painted it hot pink! I had added a varitone by then to try and tame the harsh midrange the bass got.

I was playing in a new wave band called the Jetsonz (not the band from Arizona), and it got a lot of use.

After a while I didn't use it much, and started experimenting with new pickups for the bass. I would a low impedance pickup and ran it into a Barcus Berry preamp made for piezo pickups. That sounded so good that I based my current pickup off that original experiment.

Some years later I dug the bass out of storage and made a new neck for it. It's 7 piece maple and walnut, with an ebony fingerboard, two truss rods, and graphite. It totally changed the tone of the bass for the better.

I painted the body black, and made a new pearl pickguard. It has two low impedance P pickups, with FET buffers and an op amp based pickup mixer with bass and treble controls.

Here's a song from 1980 featuring the bass. That's the bass starting the song off. (I'm playing bass, guitar, and farfisa organ).

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I don't want to hi-jack the thread, but this goes to show what you can do to alter a bass.

Here's a few photos.

Here's the body, partly stripped of its paint, and all the parts for the new neck. The neck blank was all ready glued up. You can see that the body started off as day-glo pink, and then was a sort of fuchsia. Hey, it was the 80's! :D

8-string_neck_parts.jpg


Here's the back of the neck before carving, and also before the back strap was applied to the head. You can see the scarf joint. There's no reason for the head to have walnut lams.... I just felt like it.

rough_neck.jpg


Here's the finished neck after I sprayed clear lacquer on it. The unfinished body is on my very messy work bench. You can see the new neck block, and I also contoured the lower horn. You can also see where the holes for the through body octave strings were plugged.

finished-neck.jpg


Taa daa... the finished bass, strung up with 4 flatwounds, along with some of its cousins. Yes, it was 1996. That's in our old shop in Hoboken, in the same space that Guild Guitars once occupied. If only the walls could talk!

mantaray.jpg
 
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Looks great to me! Is the Skelly rare enough to be valuable? If not, then carry on!

First issue is string spacing. Is it wide enough at either end of the fingerboard? What's the current bridge spacing? Take some measurements for us.

Second issue is finding room for the additional tuners. The lower half of the headstock looks good, but I'm not sure about the upper half. Might have to dowel, re-drill, and re-finish.

Third, more minor issue is neck strength. If it's not a super-thin flexy neck, it should be okay, especially with lighter gauge strings.

I approve! :bassist: