Intonation

It would help to know whether you've an acoustic or electric guitar. If electric, the make and model would also be helpful because it would put everyone on the same page, allowing a specific answer instead of a lot of general ones ("if you've got this, then do that, etc., etc.")

And I think you're discussing the intonation of the guitar, not indentation.

Welcome to Guitar Noise, by the way. Hope we'll see you around the rest of the Forums.

Peace

Right, my bad. It's very early. It's a electric Gibson Firebird 7.

There are a couple things about intonation...

First, intonation MUST be adjusted with new strings. There's a sound reason for this - the pitch a string makes is related to the length, tension, and mass of a string. As you play, the string gets dirty... which means it has more mass, so the pitch is lower. When it gets low enough for us to notice, we crank up the tension to put it "back" in tune.

Problem is, we spend most of our time playing below the 12th fret. So that's the part of the string that has the most mass. And when we fret a dirty string at the 12th fret, it's got less mass than it's supposed to have... so it's sharp.

Assuming you have new strings, now you have to figure out just how sharp it is - a quarter tone? An eighth? (You don't need to do this on guitars that have individual string adjustments, but on yours it will save you time). Do this for both the E strings - they may be off by different amounts.

Now look closely at the distance between the 12th and 13th frets. If a string is off by 1/4 of a half step, measure 1/4 of the distance between the 12th and 13th frets. Now multiply this by 1.05 (the math is complicated - trust me here). That's the distance you need to move the bridge piece BACK - away from the peghead. (Again, do this for both E strings)

Take tension off the strings, loosen the screws on each side of the bridge, and move it back. Move it by the amount you've come up with for each E string, tighten the screws, and tune up.

Because of the design of a Firebird bridge, you may not ever be in perfect tune. But this should get you a lot closer.

(According to Gibson's specs, the Firebird VII has a tune-o-matic bridge, NoteBoat . . .)

Edit for clarity: The tune-o-matic bridge (A. K. A. ABR-1 bridge) has individual string adjustments. NoteBoat is describing the procedure needed to adjust the intonation on a wraparound bridge / tailpiece. This procedure WILL NOT WORK for the ABR-1

As NoteBoat said, change your strings first! This MAY solve your problem with no more action needed.

If more work IS needed, here's a link to Gibson's set up guide. They don't make this easy to find on their site . .

http://www.gibson.com/backstage/tech002printable.htm

Note Boat's right...reset the distance (minutely!) on the bridge. But, for sure, the stock bridge on the F'birds aren't all that happy...so you may want to buy a "real" one!

Cat

Note Boat's right...reset the distance (minutely!) on the bridge. But, for sure, the stock bridge on the F'birds aren't all that happy...so you may want to buy a "real" one!

Cat

Are you looking at the same guitar I am????

http://www.gibson.com/en-us/divisions/gibson%20usa/products/designer/firebirdvii/
http://www.gibson.com/en-us/Divisions/Gibson%20USA/Products/Designer/FirebirdVII/specs/

Looks like Moonrider is right - I didn't catch the "VII" (and used to own a Firebird without any Roman numerals myself - so I was remembering the bridge)

With a fully adjustable bridge, you move the saddle piece toward the peghead to correct a flat fretted note (compared to the harmonic); you move it toward the tail to correct a sharp one. You can actually make these adjustments without taking off string tension - although you'll have to re-tune after you're done- so you can be a lot more precise than you can with the one-piece saddles found on the old Firebirds, SGs, etc.

Looks like Moonrider is right - I didn't catch the "VII" (and used to own a Firebird without any Roman numerals myself - so I was remembering the bridge)

Whew. I was so confused . . .

Sure is a pretty guitar too!

Thanks guys, I changed my strings and took your advice and it really helped a whole lot. It's still not perfect though. Any advice for the finishing touches?

First, intonation MUST be adjusted with new strings. There's a sound reason for this - the pitch a string makes is related to the length, tension, and mass of a string. As you play, the string gets dirty... which means it has more mass, so the pitch is lower. When it gets low enough for us to notice, we crank up the tension to put it "back" in tune.
Not to mention that the extra mass builds up in unevenly distributed lumps along the string. Makes a real mess of intonation. (And tone.)