Replacing fretless neck - lined 20 for unlined 24 – ?

[Full Beam]

Hello all,
I adore my Fretless Fender Jazz Bass, but occasionally, I require a few higher notes, and I prefer an unlined neck. I’ve been searching for an alternative bass that meets these requirements, but now I’m contemplating sourcing an unlined 24-fret fretless neck instead, and having a local luthier fit it. I’d greatly appreciate your insights on whether this is a viable option or not - is it even feasible? If it were possible, where could I find such a neck?
Many thanks!

 

[mikezimmerman]

To get 24 frets on a Jazz neck, you would need to have a fretboard extension. Warmoth offers that as an option on their Fender-style necks, and of course you can get the necks with either lined or unlined fretless boards. Warmoth necks are compatible with Fender bodies, so you should be able to just bolt it on. Be aware, though, that it may be hard to reach the upper positions with a 24-fret extension, since the lower cutaway on the body is not that deep.

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[nonohmic]

Intonating the high notes on a 24 fret unlined jazz neck extension well into the body is either gonna be really tricky or really impressive.

 

[Gilmourisgod]

Yep, definitely some kind of odd "thumb position" required to get to the upper frets, but I can't say enough good things about Warmoth necks. I've had one on my fretless Frankenjazz for almost 30 years, and it's the most stable wood neck I own. They use pretty thick fingerboard stock, so the extension is plenty solid. Measure your neck pocket carefully to make sure it fits though. I bought a Warmoth body and neck, so they were a perfect fit, but I don't know if all the Warmoth necks are drop-in compatible with all Fender eras.

 

[T_Bone_TL]

If having a luthier do it, could simply route off the fingerboard and put on a new one.

Might cost more than remove neck, sell neck, buy different neck with fingerboard extension, though.

 

[Bruce Johnson]

Hello all,
I adore my Fretless Fender Jazz Bass, but occasionally, I require a few higher notes, and I prefer an unlined neck. I’ve been searching for an alternative bass that meets these requirements, but now I’m contemplating sourcing an unlined 24-fret fretless neck instead, and having a local luthier fit it. I’d greatly appreciate your insights on whether this is a viable option or not - is it even feasible? If it were possible, where could I find such a neck?
Many thanks!

Jeremy Kirsch @Freekmagnet has done a few of those conversions. Putting a new unlined fretless 24-fret length fingerboard onto an existing Fender neck. The fingerboard extends about 2" beyond the end of the heel. He attached a maple block under the overhanging end to strengthen it and keep it stable. Then cut a notch in the body behind the neck pocket to clear the maple block. It works, it's a nice conversion. You can PM him for more info.

 

[darwin-bass]

Props to you OP. I have enough trouble playing my unlined fretless in tune at the 14th fret. 24th fret? Not a chance.

Have you considered getting a bass that not only has the extended fingerboard but has a body built to access those upper notes like an Ibanez Portamento?

 

[FullumMusic]

Definitely can't just drop in a new neck that's 24 frets long. The scale of the bass is 34" from the nut to the bridge.

If you put a neck with more frets in, a.k.a. a longer neck, the neck pocket in the body would need to be re-routed so the base of the neck is closer to the bridge to maintain the proper scale length. In other words, the 20th fret of the longer neck needs to be the same exact distance from the bridge as in the 20 Fret neck.

Otherwise, you need a neck with a fretboard extension: Neck is 20 frets long, but the fretboard is longer, extending past the end of the neck. Invalid Link Removed I don't know how stable they are beyond where they're attached to the neck vis a vis ski-jump warping.

And then with either of those options, the upper frets might be hard to reach because the lower cutout of the body is still only designed for 20 frets.

It might be better just to get a 24 fret fretless with two single coils from another builder/manufacturer. Off the top of my head, Sadowsky and Sire make 24 fret fretless Jazz basses, at different ends of the price spectrum.

 

[eeyorebass]

Jeremy Kirsch @Freekmagnet has done a few of those conversions. Putting a new unlined fretless 24-fret length fingerboard onto an existing Fender neck. The fingerboard extends about 2" beyond the end of the heel. He attached a maple block under the overhanging end to strengthen it and keep it stable. Then cut a notch in the body behind the neck pocket to clear the maple block. It works, it's a nice conversion. You can PM him for more info.

He documented the project in his own thread. Start here and scroll down the page for the finished product.

A Warmoth neck with the 24 fret extension will drop in, but I'm not sure about an unsupported extension like they use. It seems like it would flex and potentially bow upward if the humidity swings the wrong way or the wood decides to settle funny.

I've never had an issue with their 21 fret extensions, but those extra 3 feel like a bridge too far.

 

[Pings Bass]

Props to you OP. I have enough trouble playing my unlined fretless in tune at the 14th fret. 24th fret? Not a chance.

Have you considered getting a bass that not only has the extended fingerboard but has a body built to access those upper notes like an Ibanez Portamento?

I love my Portamento, but I struggled with the side markings at first. Once I got used to that, it makes sense, and is definitely useful if you ever want to play up the full 2.5 octave (!) neck. And it indeed has full access up there if you ever want to wander up into the stratosphere. Frankly all that neck is wasted on me, especially since I have a 6. Too shrill way up there.

 

[GretschWretch]

Unless you are married to the idea of a 34" scale, since it is a fretless bass you can get your additional notes by cheating the bridge forward for a shorter scale.

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