Old Gibson Intonation

[MikeB]

I've read here that a number of older Gibson models had bad intonation. #I've never noticed this on my early 20s A model (I must be tone deaf), but today after stringing it up with new strings, instead of checking the tuning only on the open strings, I decided to check all the frets, all the way up the neck. I have a problem

My readings show that with *the open string tuned exactly to pitch*, according to my electronic tuner, it plays FLAT on the lower frets, with the flatness (?) decreasing as I progress up the neck. #In other words, the first, second, and third frets play flatter than the fourth, fifth, and sixth, until it is back on the money at the 12th fret.

Is this the way the erroneous fret placement usually manifests in these models? #Or do I have another problem?

[Jim Garber]

I have heard from a well-respected luthier that some of the Loar-era mandolins, esp the snakeheads have thei fretboards out of wack. He checked out my 24 F4 and showed me how it was the case. I believe that my 23 A2Z might have the same problem. The solution is a new fingerboard.

Not sure if this is the case with all 20s Gibsons.

Jim

[uncle ken]

There is another thread (http://www.mandolincafe.net/cgi-bin/ikonboard.cgi?act=ST;f=7;t=15258) on this subject. Also this article (http://www.vguitar.com/artists/details.asp?ID=140) has some info on this.

[danb]

I had a snakehead ajr from 1924 with that same problem. Frets 3-5 are in the wrong place, basically. a new fingerboard or a much more expensive refret moving the wires will fix it. Even the Loars have been known to suffer mildly from this problem. To see it, check to see if 3-5 are all parallel..