Intonation Issues :-(

PopaWoody · #1 06-04-2009, 02:02 PM

I have this beast that will not dial in to save my a$$. I have a 4 string Ibanez SR300DX, that I completely love for the fast jazz neck. I have been neglecting it lately. So I tune it up to Eb,Ab,Db,Gb half step down.

I get out the chromatic tuner calibrate it. then check the intonation. Sharp by at least 20 cents. I tuned open strings, at the 12th Harmonic it is very close, 12th fret forget it its sharp as all get out. only the G string is even remotely close.

Here is the kicker, for kicks and giggles I checked the notes down the length of the neck. It appears that even at the first fret I am off just as much as at the 12th. Anyone have any ideas why this is?

The Nut is secure, the action is pretty good for what this thing is. 3/16th" or so at the 24th 1/16th" at the first. I have adjusted the saddles back and it did get a little better, but at the end of travel its still sharp. I cannot get any strings to go flat intonation wise.

Ready to pull out what hair I have left.

FWIW I check my Yamaha and it is dead nuts on the money.

Steveaux · #2 06-04-2009, 03:10 PM

Pull the bridge and remount it about 3/8" to 1/2" farther back.

dmusic148 · #3 06-04-2009, 03:15 PM

Quote:

Originally Posted by Steveaux

Pull the bridge and remount it about 3/8" to 1/2" farther back.

No. Get a new set of strings. This is at least the 2nd post like this this week which was cured with new strings.

bovinehost · #4 06-04-2009, 03:18 PM

Second the strings concept.

**T. B. Player** · #5 06-04-2009, 03:20 PM

Get new strings, but be prepared to do the bridge thing too.

I'm a stickler for intonation on my fretless simply because there are no frets to cheat on, so it has to be "dead on." My six string fretless would not set up properly...it seemed like the saddle needed an extra 1/8" of room - so I moved the bridge back 1/4 inch to give me the saddle adjustment room necessary. It now sets up perfectly. Any problem with harmonic articulation lets me know it's time for a new set of strings.

Z

PopaWoody · #6 06-04-2009, 03:54 PM

You sir are probably right, although these strings are not that old. No way am I going to remount the bridge....

Quote:

Originally Posted by dmusic148

No. Get a new set of strings. This is at least the 2nd post like this this week which was cured with new strings.

PopaWoody · #7 06-04-2009, 03:57 PM

This is what I find weird, Harmonics are fine, right on the money, fretted its 15-20 cent off.

Quote:

Originally Posted by T. B. Player

Get new strings, but be prepared to do the bridge thing too.

I'm a stickler for intonation on my fretless simply because there are no frets to cheat on, so it has to be "dead on." My six string fretless would not set up properly...it seemed like the saddle needed an extra 1/8" of room - so I moved the bridge back 1/4 inch to give me the saddle adjustment room necessary. It now sets up perfectly. Any problem with harmonic articulation lets me know it's time for a new set of strings.

Z

ByF · #8 06-04-2009, 08:03 PM

Was the intonation set after you detuned it, or before?

Ed

PopaWoody · #9 06-04-2009, 08:54 PM

I normally keep this one 1/2 step down and have not checked it in a while. Never tried to set the intonation before. I don't think the intonation was ever a problem. BUT there is some new material in the set list, which is tuned 1/2 step down. So I went back to this bass to learn the new material. I tuned it to the sustained open A in Rooster from AIC, started to warm up a lil that's when I noticed it was sharp on fretted notes.

Broke out the old trusty Korg, and noticed these issues. I am going to try a new set of strings on it this week and see what happens. This is my third bass, Not my main so we will see what happens.

If my thinking is correct, when you have a bass that is tuned down. You have less string tension, requiring less pressure to fret the string. Therefore your intonation would tend to go sharp. Is that right? Or am I backwards?

Maybe in the morning I will tune to 440 and see what happens.

Quote:

Originally Posted by ByF

Was the intonation set after you detuned it, or before?

Ed

Rick Auricchio · #10 06-05-2009, 11:44 AM

Harmonics should always be in tune, because you're not using frets to change the string length. A 34" open string produces its harmonic at (about) the 12th fret. More precisely, exactly at the 17" position on the string.

When you use frets, that's when the distance between fret and bridge is important. When you adjust saddles, you're adjusting for a perfect 17" distance between the 12th fret and the saddle.

What about the neck mounting? Is there a way to loosen the neck bolts, apply pressure to pull the neck slightly out of its pocket, then tighten? This gets the same effect as moving the bridge, and it may be just enough.

Lower string tension means less fretting pressure, thus less stretch, and you don't go as sharp. I wouldn't expect a half-step down to cause intonation problems. We've had Hipshot D-tuners on the E string for decades, and they don't ruin intonation.

ByF · #11 06-05-2009, 05:28 PM

Quote:

Originally Posted by PopaWoody

If my thinking is correct, when you have a bass that is tuned down. You have less string tension, requiring less pressure to fret the string. Therefore your intonation would tend to go sharp. Is that right? Or am I backwards?

Not sure about that--it makes my brain hurt to think about it. When you de-tune, because of less the string tension, the neck probably bends back more, so you have to stretch the string less to get it to touch the fret, so it goes less sharp, or more flat-- OW!

Rather than try to psych it out, I'd suggest that you put on new strings, and intonate with it tuned the way you intend to play it. That's got to be the best condition.

Ed

Steveaux · #12 06-06-2009, 02:50 PM

I mention moving the bridge because I've had to do it twice.

When I mount a bridge on a new build, I place it with the center of the available travel range at the 34" mark. I use the actual available travel, not the length of the screw. To find this, run the saddle out to the end of the screw, fully compress the spring, and mark the mid-point between the apex of the saddle and the forward end of the spring.

I change my strings every month, so I haven't experienced that particular problem ... yet.

Kevmove · #13 06-10-2009, 01:01 AM

I was having the same problem today. I thought that my bass was out of tune, so I tuned the open strings then check the intonation at the 12th fret. No problem. To my surprise, the e string was sharp at the 5th - 10th fret. After playing with it for a few minutes, I check in here to see if anyone else was having the same problem. I opted for the "change the strings" solution. It worked perfectly.