source file: mills2.txt Date: Tue, 4 Jun 1996 10:25:21 -0700 Subject: Refretting guitars From: John Starrett Ladies and Gentlemen- Common practice in guitar building is to fret the neck as if no string stretching would take place and compensate at the bridge for the stretching that takes place when the guitar is fretted at the octave (12th fret, 31st fret, whatever determines the octave for any particular instrument). This is a compromise between accurate tuning over the whole neck and ease of setting the bridge piece (comparing the pitch of the open string or octave harmonic to that of the string fretted at the octave can be done by ear). I know of no realistic way to build a guitar that has correct stretching compensation over the whole neck, but if you lay the frets out with no compensation for stretching and adjust the bridge to give correct pitch in the area you expect to play in most (rather that at the octave), you will probably be quite satisfied with the results. There are a few builders working on computerized retunable guitars, so that the artist can quickly change string tension, but these are not currently operating well enough for discriminating users. Certainly a guitar could be built in which the position of the bridge pieces were quickly adjustable to account for stretching at different locations on the neck (servo or stepper motor control or some mechanical linkage), but this seems like overkill for a relatively small problem. When a guitar is well set up (proper neck relief, nut height, bridge height, string guages, etc), the standard octave compensation is surprisingly good. Also, please do not consider movable nut pieces to compensate for string stretch. The nut should have the same function as a zero fret, and if it is accurately placed and set it will act as a zero fret. In short, put the frets where they should be assuming no string stretch from fretting, set the guitar up properly and then adjust the bridge to compensate in the middle of the most played area. John Starrett Received: from eartha.mills.edu [144.91.3.20] by vbv40.ezh.nl with SMTP-OpenVMS via TCP/IP; Wed, 5 Jun 1996 00:05 +0100 Received: from by eartha.mills.edu via SMTP (940816.SGI.8.6.9/930416.SGI) for id PAA27709; Tue, 4 Jun 1996 15:05:06 -0700 Date: Tue, 4 Jun 1996 15:05:06 -0700 Message-Id: <12960604215721/0005695065PK4EM@MCIMAIL.COM> Errors-To: madole@ella.mills.edu Reply-To: tuning@eartha.mills.edu Originator: tuning@eartha.mills.edu Sender: tuning@eartha.mills.edu