#1
Mornin' UG'ers! (or evenin' for those in better places than the US)

So I decided it was time to learn a little bit more about my actual instrument. Adjusted the action (very pleased) and moved on to intonation...which has me a little baffled.

Using a KORG CA-30 tuner. Floating bridge (Strat wanna be guitar).

Question: My understanding is if I hit the open E and tune it perfectly. I should be able to fret at the 12th, hit the string again and it result in the exact same tone.

What I'm finding is: When I hit the 12th fret, KORG is reporting the tone is higher than the open string.

With this bridge, each string has a little slider piece that can be tightened/loosened to move it back and forth. I have loosened the screw-slider thingy on the bridge (sorry, not sure what that little piece is called) and tightened it ALL THE WAY so that it couldn't be tightened anymore... regardless, the 12th fret tone stays the same on the KORG...always high. Not out of tune high, but higher none the less.

am I missing something here? Is that what it 'should' be? Or should they both match identically?

Sorry for the length - just wanted to try and explain it as best I could....

Thanks for any help!!

Example: . = Where the needle sits when string is played OPEN
: = Where needle sits when played at 12th fret
Attachments:
korg.jpg
Last edited by Slapknot at Jan 16, 2009,
#2
If the intonation is right the harmonic at the 12th fret will be the same as the fretted note at the 12th fret
#3
Quote by zhilla
If the intonation is right the harmonic at the 12th fret will be the same as the fretted note at the 12th fret



hahaha - answered before I was done adding my fantasticly artistic pic of the KORG...

Wait - so it's NOT the 12th fret it's the harmonic on the 12th fret??? I thought I was supposed to actually fret the 12th note, not just the harmonic... ?
#5
What you're missing is that the slider as you call it, which is actually the intonation adjustment for each bridge saddle, is not a loosening/tightening thing, it's a slide adjustment. If your string is right on when played in the open position, then shows that it is sharp at the 12th fret, you would then need to move the saddle back away from the neck, resulting in a slightly longer scale length for that string, and making the note fretted at the 12th lower, flattening it out.
Each note should match exactly, or as near to it as you can get it. To truely do this accurately you need a better tuner than the one you have. A strobe tuner works much better. The Korgs are nice and all, very handy, but don't show a high enough resolution to really fine tune intonation.
So for you then, just set your open strings to as close to dead on as you can with the tuner, steady green light. Then fret each string at the 12th and note if it's flat or sharp as compared to the open. If the red light is on at the the right of the green, the 12th is sharp vs. the open and you need to lengthen the scale. If the red light is on to the left of the green then that note is flat vs. open and you would need to move the saddle closer to the neck to shorten the scale.

Edit: I guess I should add that you can also check by comparing the open string to the harmonic at the 12th, but trial and error over the years has told me that this method is not as accurate as actually fretting the 12th. The reason is that you play the guitar by fretting the notes, which means pressing the strings down onto the frets to achieve the correct pitch. Doing this causes the string to stretch slightly, which in turn effects the intonation of each string at each fret. By performing a harmonic, you are not factoring in this stretch, and can wind up with slight errors in intonation which could be eliminated by performing the open/fretted 12th method.
If you were to play purely harmonics on the guitar 100% of the time, then the harmonic method would be ideal.
Last edited by LeftyDave at Jan 16, 2009,
#6
Quote by zhilla
If the intonation is right the harmonic at the 12th fret will be the same as the fretted note at the 12th fret


Wrong way there. You compare the open string to the fretted 12th. Why would you want to compare half the scale length of the string to half the scale length of the string? You're not comparing anything and they SHOULD be the same note, always. Open string notes vs. fretted 12th string notes is a valid comparison when testing intonation.
#7
Quote by Slapknot
hahaha - answered before I was done adding my fantasticly artistic pic of the KORG...

Wait - so it's NOT the 12th fret it's the harmonic on the 12th fret??? I thought I was supposed to actually fret the 12th note, not just the harmonic... ?


Correct, you fret it and compare that to the open string counterpart. Low E open vs. low E fretted at the 12th fret.
#8
Quote by LeftyDave
Wrong way there. You compare the open string to the fretted 12th. Why would you want to compare half the scale length of the string to half the scale length of the string? You're not comparing anything and they SHOULD be the same note, always. Open string notes vs. fretted 12th string notes is a valid comparison when testing intonation.



Oops sorry my bad. Well at least I learnt something today - thanks
#9
Thanks all!

So far, you're reaffirming what I thought.

Now what I'm not getting is: If I loosen the screw on the intonation slider ALL the way, I mean it is going to fall out... and I test it (open, then fret 12th) the result is a sharper note on the 12th fret.

I then tighten the screw ALL the way...I mean just keep turning, no regard for minor tweaks, tighten until the slider is as far from the neck as possible. I then test it again...it's STILL sharp... shouldnt it be flat?

Is this an indication something is wrong with the guitar?? It's only a couple months old, as are the strings on it.
#10
It's still sharp, but is it AS sharp as it was when the bridge saddle was all the way forward, closest to the neck? You should see at least some change in the pitch of the note. You don't even need to fret at the 12th to see this. Just have whatever string you're using to test tuned up to pitch open, then move the saddle piece one way, retest the note's pitch with the tuner, then move it the other way, test again. You should be able to see at least something happening to the pitch.
If you can't get the pitch to drop flat enough, then chances are good that you've got the same problem going on that I did with my strat clone. It's an Austin, 3 single coil pickup strat knockoff. Same problem as you, I couldn't get my low E saddle pulled back far enough to flatten out that strings 12th fret note. It always played sharp high up the neck. I wound up taking the saddle out for the low E and grinding away some of the rear edge of it, then installed a shorter spring so that I had more room to pull the saddle back enough to get the right intonation. The problem is in the build. Cheapo guitars like these are built on an assembly line with far less QC than a hand made one would. They just aren't as accurately built as a real Fender Stratocaster is.
#11
You shouldn't use the harmonic at all in setting intonation. After all, it will always be an octave of the open string. Where that is useful is in comparing with the 12th fret to see how much bend you are applying when playing. Careful string height adjustment, along with intonation setting is what gets you close to perfect. But the mechanics of a guitar mean you must always compromise a little bit. The compromise is less on a classic Fender bridge than on one like a Gibson as the latter does not have individual adjustment for string height.
#12
Quote by LeftyDave
It's still sharp, but is it AS sharp as it was when the bridge saddle was all the way forward, closest to the neck? You should see at least some change in the pitch of the note. You don't even need to fret at the 12th to see this. Just have whatever string you're using to test tuned up to pitch open, then move the saddle piece one way, retest the note's pitch with the tuner, then move it the other way, test again. You should be able to see at least something happening to the pitch.
If you can't get the pitch to drop flat enough, then chances are good that you've got the same problem going on that I did with my strat clone. It's an Austin, 3 single coil pickup strat knockoff. Same problem as you, I couldn't get my low E saddle pulled back far enough to flatten out that strings 12th fret note. It always played sharp high up the neck. I wound up taking the saddle out for the low E and grinding away some of the rear edge of it, then installed a shorter spring so that I had more room to pull the saddle back enough to get the right intonation. The problem is in the build. Cheapo guitars like these are built on an assembly line with far less QC than a hand made one would. They just aren't as accurately built as a real Fender Stratocaster is.


Thanks Lefty - consider this thread 'killed', but in a happy Kevorkian way... ya nailed it to - this is my first cheapy guitar. Didnt wanna dare mess with my Ibanez until I knew what the hell I was doing.

I'm gonna try doing this on the high E and see if I can get any diff results.

Thanks everyone for your help/insights!
#13
Like LeftyDave said, you probably won't get a very accurate intonation using a CA-30. At the very LEAST, get a Boss TU-12, but honestly, if you want good results, you need a Peterson.

EDIT: Another tip, change your strings before you intonate. Old strings stretch out and get funky, and that will definitely affect your results.
"When I was a kid I inhaled frequently. That was the point."
Last edited by brleealbright at Jan 21, 2009,