Jem 7v intonation problem

[jgparker]

I have it intonated at the 12th fret, so from the 1st to the 12th it is in tune/intonated BUT from the 12th to the 24th fret it starts rising sharply to almost a full half tone on the 24th!
What needs to be done? Do I need to use the truss rod?HELP!!

[nuno]

intonate it at the 24th, and be sure your string action isn't set too high

[thresher]

Try intonating with a decent tuner by matching the fretted notes the 2nd and 14th fret. This should get all *fretted* notes reasonably close.

If after doing this you notice that the open strings are off in relation to fretted notes, it would indicate a nut placement problem. If this were the case, it would explain why the standard 12th fret harmonic intonation method doesn't work for you.

[Rich]

12th fret intonation doesn't work because it doesn't take much of the scale into account.

A Peterson manual will recomend 5th and 17th fret. The last few frets will still be a little sharp but not as much as with the antiquated 12th fret method.

I always liked last fret intonation because it leaves the lastm frets in tune where they will be sharp in any other method. You can always add pitch with pressure but you cannot take pitch away. Using last fret the middle range of the neck will be a little flat though.

That's just how guitar necks are. Quite imperfect.

[jgparker]

Thanks everyone for the advice. I will try these techniques. Guess I should try these techniques using a new set of strings rather than trying to intonate on a month old pair right?

[smooth55]

Most assuredly...