Earvana nut on a short scale guitar?

Seziertisch

I saw mention og someone doing this and being pleased with the results on a Thomann review.

I have a Blackstar Carry On, which is super portable but suffers somewhat in terms of intonation from its short scale (18 frets, 20.7” scale) and was wondering whether this might be of use.

I guess I should go to the source :-) @FelineGuitars What say you?

guitargeek62

I don’t think they’ll be much use as the compensation will (should?) be determined for the assumed scale lengths on the type they’re being installed on - 20.7” is quite outside of a ‘typical’ range!

What’s the issue with the intonation? Is it spread out across the neck, or…?

Funkfingers

My two penn'orth. 

1) The nut is probably cheap plastic and not especially well slotted.

2) The Tune-o-Matic style bridge does not permit sufficient travel of the saddles to adjust correctly.

3) There may be a mismatch between the fingerboard radius and the bridge.

Seziertisch

Funkfingers said:

My two penn'orth. 

1) The nut is probably cheap plastic and not especially well slotted.

2) The Tune-o-Matic style bridge does not permit sufficient travel of the saddles to adjust correctly.

3) There may be a mismatch between the fingerboard radius and the bridge.

1) It’s a bone nut as stock, it has been dressed by a professional.

2) Tuneomatic was replaced with one from ABM which has an extended range. The g string currently in there is unwound and the saddle is adjusted as far back as it goes, a changeover to a wound g is on the cards.

3) Don’t think there is a mismatch, both are 12” as far as I know. The guitar was designed by Gordon Smith so I’d be surprised if they had decided to go for a mismatched bridge and radius.

Seziertisch

guitargeek62 said:

I don’t think they’ll be much use as the compensation will (should?) be determined for the assumed scale lengths on the type they’re being installed on - 20.7” is quite outside of a ‘typical’ range!

What’s the issue with the intonation? Is it spread out across the neck, or…?

Ignoring the g string (which would likely benefit from a wound string), there is a sourness to chords as you move up the neck which is more pronounced than on a regular scale.

By comparison my Les Paul has a Earvana nut and I really notice the difference when I change from it to any of the other guitars I own.

ICBM

How well cut is the existing nut? It’s extremely critical on these very short scales - it has to be as low as possible short of being actually too low (if that makes sense!). I’ve just done one of those daft Daisy Rock ‘heart’ guitars, and with the nut even lower than I would normally aim for it does actually play in tune quite well, even with 10s on.

The Earvana should still make a difference though, as it addresses the string flexibility issue - whereby a thicker/less flexible string plays flat when open due to the nut groove constricting it, hence you’ve actually tuned it sharper than you think you have, which makes fretted notes sharp. That will apply just as much, and maybe more, on a short-scale guitar.

Seziertisch

ICBM said:

How well cut is the existing nut? It’s extremely critical on these very short scales - it has to be as low as possible short of being actually too low (if that makes sense!). I’ve just done one of those daft Daisy Rock ‘heart’ guitars, and with the nut even lower than I would normally aim for it does actually play in tune quite well, even with 10s on.

The Earvana should still make a difference though, as it addresses the string flexibility issue - whereby a thicker/less flexible string plays flat when open due to the nut groove constricting it, hence you’ve actually tuned it sharper than you think you have, which makes fretted notes sharp. That will apply just as much, and maybe more, on a short-scale guitar.

I think the nut is okay, the guy who dressed it is a mandolin player by trade so is used to dealing with shorter scale instruments.

I found a wound string of appropriate thickness in my string box and put that on this morning. It is a big improvement. 

I still think I’ll give an Earvana nut a spin at some stage. 

FelineGuitars

I think that the earvana certainly really helps out where the strings feel looser and are easily sharpened like on a drop tuned instrument , and possibly conversely on a shorter scale one too although I haven't tried it myself yet

ICBM

Seziertisch said:

I found a wound string of appropriate thickness in my string box and put that on this morning. It is a big improvement.

Yes, a plain G is always the worst since it’s both the most affected by the nut being too high, and the least flexible so most affected by the groove.