Discussion in 'Hardware, Setup & Repair [BG]' started by lo-end, Jul 28, 2001.

  1. lo-end


    Jun 15, 2001
    Hi Im wondering what is the proper way to intone a bass... do you tune the harmonic to the 12th fret or the open string to the harmonic or the open string to the 12th fret? I just intoned my bass with the open string to the 12th fretted note and I dont think I did it right. I tuned it with harmonics and it was perfect but I played some notes on the frets and they sounded out of tune...

    So which notes do you want to be the same? 12th fret harmonic, 12 fretted note, or open string? Yes, I know how to move my saddles and everything...
  2. john turner

    john turner You don't want to do that. Trust me. Staff Member Administrator

    Mar 14, 2000
    atlanta ga
    hey there

    intonating one's instrument is one of the most important aspects of setup that you can do yourself, and it's not too hard, although it can take a bit of time.

    1. tune the open string to a tuner.

    2. play the 12th fret harmonic - notice that it will be in tune if the open string is in tune.

    3. fret the 12th fret and compare it with the 12th fret harmonic - if the fretted note is sharp, move the bridge saddle back a bit, if it is flat, move the saddle forward a bit.

    4. repeat 1-3 until the 12th fret harmonic and fretted note are in tune.

    you'll never be _perfectly_ intonated from first fret to last fret - some will always be out a bit no matter what you do - but there are a few things you can do to make your intonation more even along the string length.

    1. make sure your nut is filed low enough. if you don't know, the nut is the thing at the top of the bass, by the headstock, that holds the strings in line (at the position where the 0th fret would be at the end of the fretboard). if the nut is too high, the notes on the lowest frets will be sharp when the rest of the instrument is intonated properly.

    2. us taperwound strings. tapers make for a better intonation, since there is less string diameter over the bridge saddle, making for a more precise witness point.

    here's my famous saddle witness-point "lecture" along with a visual aid ;) :D

    taperwound strings intonate much more accurately than non-tapers, especially on the bigger strings. they provide a more concise witness point to the bridge, which in turn forces only harmonics that are closer to multiples of the fundamental to sound.

    first off, some theory...

    when an ideal, perfect string is plucked, only frequency multiples of the fundamental will sound. the fundamental is directly related to the length of the string, and all the harmonics are multiples of the fundamental, all in tune and sound pretty, regardless of how high they are.

    with a real string, the witness point of the string to the bridge, along with the fact that real strings are not infinitely flexible like a "perfect" theoretical string, both work together to cause a sort of "gray area" for the string, where it is bending, not at a perfect point over the bridge, but more of a curve, due to the thickness of the string.

    this gray area reflects in the fact that the actual length of the vibrating portion of the string is not clearly delineated. this causes higher harmonics to be present that are out of tune with the fundamental. a smaller witness point and a sharper break angle will cause this gray area to be smaller, and keep the higher harmonics more in tune with the fundamental.

    a pic will help explain this better...

  3. seamus


    Feb 8, 2001
    Good cover JT, that's about as thorough an explanation as I've ever read re: intonation.
  4. john turner

    john turner You don't want to do that. Trust me. Staff Member Administrator

    Mar 14, 2000
    atlanta ga
    i do what i can, thanks :D
  5. Thanks John Turner for the Lesson, :)
  6. Speedbird

    Speedbird Supporting Member

    Jul 10, 2000
    Northern Virginia
    Also check out that alternative intonation thing in this months BP magazine.
  7. Suburban


    Jan 15, 2001
    lower mid Sweden
    Thanks, John, that was very enlightening!!

    Wish to add one thing, though:
    Using a fretted instrument, most notes will inevitable be out of tune, because no human or human made machine will ever be able put place all frets exactly on the proper spot.
    With an unfretted instrument, most notes will inevitably be out of tune, because your finger is blunt. But! There will be times when you hit it, and you will, almost, levitate.:rolleyes:

    Hence, intonating the instrument is crusial, but will never be really good:(
  8. DiegoMcgee


    Oct 20, 2001
    Providence RI
    That was awesome!!!
    I've never tried to
    do my own intonation before but I'm
    going to give it a try. I'm also going to
    convert from a b-e-a-d-g tuning to a
    e-a-d-g-b tuning. I hasn't before because
    of buzzing on my low b string at open
    through the 3rd fret.Is there anything
    else I should know before I try this.
    Is their a preferred set of strings to use
    for this type of set-up.
    jim obrien
  9. ZuluFunk

    ZuluFunk Supporting Member

    Apr 14, 2001
    Most useful thread I've read here, JT. I see it's been up a while.

    I sent my bass into the shop but it sat for a while with no work. I took it back and did it myself. I wasted time checking to see how the note was effected based on which direction I moved the bridge. I figured it out eventually!!!

    Only problem, the head on one of the screws (A-string) is stripped out and hard to turn. It's been that way. I'll need to replace it.
  10. Mike N

    Mike N Missing the old TB

    Jan 28, 2001
    New York
    The new BP mag(Jan 2002)has an article on p.74 about checking/setting intonation.Ive read the article 3 times and nowhere did it even mention the 12th fret harmonic.Simply put,BP's article tells the reader to tune the open string with an electric tuner,and check the tuning of the 12th fret note.If the notes arent the same,they tell you which way to move the saddle,then re-tune,re-check,repeat as necessary etc.......

    Funny,Ive always used the open note,harmonic,and fretted note(as JT suggests)to intonate my Bass.I think BP may have missed something here.
  11. Do you have to loosen the strings when moving the saddles up/down or forward/backwards?
  12. Suburban


    Jan 15, 2001
    lower mid Sweden
    Depends on the bridge.
    With a Fender standard, there is no need to loosen strings.
    With a LightWave s2, there is!
    And there are lots of bridges where you don't really have to, but it helps.
  13. bizzaro


    Aug 21, 2000
    All three should be in tune..The Open...The 12th Fret Harmonic...And The Fretted 12th. As JT stated.:rolleyes:

    Keep in mind that you are not really intonating the bass, but the strings to the bass. IE..You need check/intonate at every string change. It is not as though you do it once and the bass is good to go forever. Different guage's and brands will usually always need adjustment. And low end ---be careful with those new strings. I would hate to see you have to decide on another set. :eek: Which strings did you end up with?;)
  14. If your bass is properly intonated, the distance from bridge -> 12th fret should be exactly the same as the distance from nut -> 12th fret.

    But i am not sure abouth 2-octave basses..
    i think the 24th fret would be at 2/3rd but i am not sure..
  15. geshel


    Oct 2, 2001
    1. No - the distance isn't exactly the same, that is why you have to set the intonation! If it were all the saddles would be in the same place.

    Setting the intonation involves making the bridge -> 12th fret distance a little longer than the distance from the nut to the 12th fret. This is because when you play the note at the 12th fret, you're stretching the string a little bit, so it goes sharp. So you need to lengthen it a little to compensate.

    2. 24th fret is (roughly) 1/4 the way from the bridge to the nut.
  16. geshel


    Oct 2, 2001
    One thing I'd add, JT, is that after moving the bridge saddle, I have found it necessary to re-tune the string a little. Moving the saddle back makes it a little sharp otherwise. So I move it, retune, check the intonation, move it, retune, check, etc. :)

    Also, I don't compare the 12th fret note to the harmonic - I just use the tuner. Make sure the open string is in tune, then check the 12th fret against the tuner. Once it says so, I double check at the 24th fret (although it's totally possible that not every note on your bass will be perfectly in tune).