perfect intonation

hstiles · #1 08-27-2003, 10:45 AM

I have a pair of Fender's

Mexican Jazz 4 standard and American Deluxe V.

Both basses never seem to sound perfectly in tune to me. I tune ADGCF with 45 - 105 guage (130 on B) I like a straight neck and a bit of fret buzz for attack.

Now, open string, twelfth fret harmonic, 19th fret harmonic sound perfect and are pretty much bang on - a few minor deviations due to the mass of the string accepted. Twelfth fret held down is in tune.

However both basses sound a little bit out when I'm playing and it's driving me up the wall.

I can't have picked up two lemons and the basses sounded fine when in the shop, etc... my problems have arisen from dropping the tunning.

Aaaarrgghhh!!!

theydolph · #2 08-27-2003, 12:49 PM

As far as I know you will never get a fretted instrument EXACTLY in tune. I would suggest playing for someone else and ask them if you sound alright chances are you're just sensitive to it.

**john turner** · #3 08-27-2003, 03:24 PM

well, first off, the harmonics will be in tune if the open string is in tune. that's just a function of the physics of the string, and is the same with a good bass or a bad one.

the thing you need to check is the harmonics compared to their fretted counterparts - both 12th and 19th.

another thing to look at is the nut height - if the nut is cut too high it could cause the lowest few frets to be sharp with the instrument in tune.

chump stain · #4 08-31-2003, 01:22 PM

I'm getting the same problem on my Dean Rhapsody BB4. I tune it DGCF and I adjusted the intonation the best I can, but the first couple frets are a little sharp.

Thanks JT for the nut response, I didn't think that would be a problem, but that's probably where it's comming from. I'm using Heavy gauge Elixers, I think it's a .110 E string or something.

...So, all I have to do to fix the problem is get the nut cut deeper???

kurosawa · #5 09-06-2003, 10:01 AM

Yes, no bass is ever perfectly in tune. There are systems to make things easier on the ears in our tonal system, like BFTS, which just trades normal compromises for others. Neither normal nor BFTS compromises will make most listeners cringe. However, nasty things like nut slots being too high need to be attended to on every bass that doesn't have a zero fret, or else intonation will suck out loud (the lower the fret, the sharper the error).

**john turner** · #6 09-06-2003, 10:12 AM

Quote:

Originally posted by chump stain
I'm getting the same problem on my Dean Rhapsody BB4. I tune it DGCF and I adjusted the intonation the best I can, but the first couple frets are a little sharp.

Thanks JT for the nut response, I didn't think that would be a problem, but that's probably where it's comming from. I'm using Heavy gauge Elixers, I think it's a .110 E string or something.

...So, all I have to do to fix the problem is get the nut cut deeper???

yeah, just a bit. be careful, you don't want the nut deeper than the height of the first fret or you'll need to get a new nut.

kurosawa · #7 09-06-2003, 10:28 AM

Ditto on John's advice. Fret files are expensive, you can get drill bits the right size and use them as files, and they take off very little per pass. Check a drill table. Also, measure the height of your first fret, then use automotive feeler gauges stacked to at least .005" higher than that first fret for starters. Jam it under the other 3 strings just behind the nut to limit how deep you file the slot. Make sure you keep the angle of the slot downwards from the fingerboard side (highest point) toward the tuner (just a taste lower) to keep it from buzzing.

chump stain · #8 09-06-2003, 02:31 PM

thanks a lot for the help guys!

I have all the tools at work to do it. I'm pretty sure we have some small rat tail style files too. They should work.