Ovation Acoustic Guitar Neck Angle Assessment

Well, well well.  What do we have here?

It's an Ovation guitar!  We don't see these a lot on the Crawfish Instruments workbench.

Just looking at this picture makes me think of two artists:  Ray Davies and Cat Stevens.

This particular guitar is from about 1986 - it's an Ovation "Ultra."  It's in super nice shape.  The owner, in fact is a big Ray Davies fan and that's one of the reasons he bought it.

The main feature that makes Ovations unique is the patented 'bowl' back.  It's plastic!  The bowl helps cut down on acoustic feedback when playing the guitar amplified.

I think this is one of those instruments that causes a bit of controversy.  Personally, I think it's pretty neato.  And I did grow up watching a lot of players using them, so for me, it brings back a lot of memories.

Anyway.

The owner is complaining of high string action on this guitar.

So I whip out my trusty measurement gauge, and...I think this is a personal record measurement - I see about 11/64 at the 12th fret on the low E.  For an correct average height, I'd expect something in the range of 5/64 or less, so we have something that's verging on the totally unplayable.

The guitar was dropped at some point, and there was a previous repair to the neck-to-body-joint.  The owner said a previous repair person "glued it on."  That's a little bit of a red flag to me, since US-made Ovations such as this one have bolt-on necks and shouldn't need to be glued.

I could tell almost immediately that the neck set is incorrect.  All of the shims under the saddle have been removed, yet there is still incredibly high action.

Now to figure out how bad the set is.

"Neck set" on any string instrument refers to the angle that the neck is at in relation to the body. The neck set determines the string action (height) from the fretboard and is the most critical element with regards to playability.


Some arch-top instruments have a steep "upward" neck set to clear the top. These instruments - violins, violas, cellos, arch-top guitars - also have raised bridges. The steep neck set contributes greatly to the tone on these instruments.

Flat-top acoustic guitars, as well as non-archtop guitars have a less steep neck set. Their bridges are lower, and the strings run in a 'flatter' plane in relation to the body.

To check the neck set, we use a straightedge running parallel to the strings.  If the set is good, the edge of the straightedge should just touch the top of the bridge.

Here's a closer view.  You can see the straightedge falls well below the top of the bridge.  I measured it at about .125 inches.  The guitar's neck will need to be reset.

A reset involves removing the neck, and shaving material off the neck (the bottom of the neck in this case) to correct the angle.

Almost every acoustic guitar will need a neck reset at some point in its life.  Depending on the string gauge and other factors (humidity and temperature the instrument is exposed to on a regular basis), about 20-25 years between neck sets is common.  It requires knowledge and precision to reset a neck, but it's not rocket surgery to understand the how and why of performing one.

In this case, it should be easier since the neck is bolted on.  Most acoustic guitars (Martin, Gibson, Guild) have glued-on necks and require more skill to remove the necks.  So hopefully (the previous glue job notwithstanding), this one will be straightforward.