Finding the right neck relief

Discussion in 'Hardware, Setup & Repair [BG]' started by Naxn, Dec 19, 2013.

  1. Naxn


    Dec 19, 2011
    Los Angeles
    Preface: basically my goal is to fine tune my setup. I don't use standard tunings and string gauges, so there really has to be a method to finding the best setup for each instrument/player.

    1. The neck doesn't have a back bow since I cannot think of any circumstance when that would be desirable
    2. The bass is played with somewhat consistent technique
    3. Nut, saddle height and frets are all ballpark where they should be.

    I've heard/read "set the relief to the thickness of a business card" or "0.XXX inches" over and over, but there has to be a better way to figure out what relief you should have based on your specific instrument and your playing style. I've been searching for the answer for a while now, I have yet to find anyone go into any depth on the subject.

    So I've been doing some thinking and thought I'd ask y'all if this sounds like I'm on the right track.

    If you have too little relief, I would think you would get string buzz in the lower half of the neck, most likely increasing as you move lower, until the first fret.

    If you have too much relief, I'd think you'd get buzzing starting from the most concave point in the neck (somewhere around the middle of the neck) and up.

  2. Ric5

    Ric5 Supporting Member Commercial User

    Jan 29, 2008
    I convert 4 string Rickenbackers to 5 string basses.
    And just when you get it set right the humidity levels change and the neck moves.
  3. MrRubi04

    MrRubi04 Supporting Member

    Dec 30, 2011
    Brewster, NY
    As I understand it, relief is to allow space for the string to move in while it is vibrating. The greatest movement will be in the middle of the 'speaking length' of the string. The shorter the speaking length, the less the movement will be; therefore the greatest relief should be in the middle of the neck because when you fret the string up at the top of the neck, that produces the greatest speaking length. You with me? So, if you don't have enough relief, you will get fret buzz; too much relief and you get nothing but bad action! The string will be higher off the fretboard than necessary. I'd have to look it up, but I thing it's 3/64" UNDER the string at the 7th fret (middle of the neck).
  4. Naxn


    Dec 19, 2011
    Los Angeles
    I'm pretty sure scale length, pitch, number of frets and string gauge would all affect that measurement. That's why I'm looking for a process to find the correct relief for any particular bass.

    So, by this logic, one should set the relief by playing the lowest (thickest) string, open (although I'd probably suggest at the first fret to completely eliminate the nut if there is one) and find the sweet spot just before that string starts to buzz. Again, this is assuming frets are level and saddles are ballpark.

    Any more thoughts?
  5. wmheilma


    Jan 5, 2010
    I have a very non scientific way to do this. Look down the neck like the barrel of a gun. It should be almost straight and not have a big bow shape or any weird kinks at one fret or another. Then push a string down at the second fret or so with your left hand. Stretch your right hand as wide as you can from pinky to thumb. Put your pinky on the string up at the 12th fret. Tap with your thumb. It should have enough relief to make a click. It should not already be flat on all the frets. Repeat on different strings and different parts of the neck. Do it on a bass that plays well for you. Do it on one that plays poorly. You'll get an eye and a feel for set up, so when you make adjustments for seasonal weather changes or a new string gauge you have a clue. I've never had a set of feeler gauges, but I can get my basses to play really well.
  6. elBandito


    Dec 3, 2008
    Rotten Apple
    First things first, you need a nice level fretboard for the measurements to be meaningful. Once I learned to level and dress the frets myself, I realized how setups are just shooting in the dark without a leveled neck.
  7. bassdude51

    bassdude51 Supporting Member

    Nov 1, 2008
    Central Ohio
    A general statement. For light touch and attack, very little relief to a straight neck. For heavier touch and attack, one or two business card gaps around fret #8 or #9.

    It's best to not get too hung up on relief because necks being made of wood change almost daily according to temperature and humidity.

    Any kind of up tuning or down tuning changes relief dramatically. The MusicMan truss rod wheel is so cool for quick and easy tweaking for neck relief.
  8. Neck relief is enTIREly personal. No one figure will cove all. No one formula will. I set my neck relief, string height, etc in the process of settin my bass up. I make it feel right. To ME. Then? Take measurements. To recreate that feel, or close, no matter what bass I play, etc. My main tunin for my projects goes from standard, to half step down, to all the altered tunins out there. I set my bass up fer standard, play all tunins with that setup. Whatever yer main tunin is? Make that feel "right". Then measure your setup an maintain. One formula jus simply won't work. Too many players, instruments an choices. That's why there isn't a standard formula.
    Stevenk likes this.
  9. pedroims


    Dec 19, 2007
    According to Roger Sadowsky: ''... Sadowsky says most people assume you can tweak the action by manipulating the neck truss rod, but that's not true. The only reason to adjust the truss rod is to make the neck properly straight, he says, which is almost straight but with a bit of relief. If the neck is too straight, it will buzz in the first position. To adjust the relief, Sadowsky slowly loosens the truss rod
    an eighth of a turn at a time until the first position plays cleanly.

    Once the relief is set,Ó says Roger, the proper adjustments can be made to the action...''

    So there you go, set the neck completely flat then lose the truss rod slowly until the first position is clean. After that set the action by adjusting the height string in the bridge.
  10. scottbass

    scottbass Bass lines like a big, funky giant

    Jul 13, 2004
    Southern MN

    +1 and +1. Neck relief (controlled by the truss rod tension) is to prevent buzzing. Action is controlled by saddle height. If your fingerboard/frets are not adequately level, you will need more more neck relief. Too much neck relief and you may not be able to set your action as low as you'd like.

    The Sadowsky method will give you the minimum possible neck relief...optimized for your particular bass, strings and playing style. The Fender factory setup is 0.012 inches (0.305 mm) measured at the 8th fret when the string is pressed to the headstock side of the first fret (a capo works well) and to the bridge side of the last fret (using your finger). I have always found the Fender spec to work perfectly well on all basses, not just Fenders. It allows me to set the action - using the saddle screws - as low or as high as any reasonable player would want.

    If you set the relief as described either by Sadowsky or by Fender and you can't get your action low enough before the saddles bottom out against the bridge, that is an indication that your bridge may be too high or your neck may need shimming.
  11. Turnaround

    Turnaround Commercial User

    May 6, 2004
    Toronto Canada
    Independent Instrument Technician, and Contractor to Club Bass and Guitar - Toronto
    First half of this is about right. But the second half isn't.

    The neck is anchored to the body. So any flex in the neck will be between the body joint and the nut. When you bow the neck with too much relief you are not causing the most concave point of the neck to shift lower in relation to the body. You are relaxing the counter tension to the strings causing the entire neck to bow upward. Imaging you were stringing a bow (as in a bow and arrow). You have the bow lying on the floor and you are standing on one end. As you string the bow it bends upward, but nothing changes where you are standing on it.

    In the case of the bass, nothing is changing from the body joint toward the bridge. As you increase the relief, the neck is bowing up, adding more clearance even on the upper frets. So, strictly speaking, too much relief will not cause buzzing in the upper frets.

    But because the additional relief has caused increased clearance even in the upper frets, folks lower their saddles to get better action and that's where the buzzing comes in. If you have too much relief and have lowered the saddles to compensate for higher action, you will buzz out on the upper frets. It's a question of balance - just the right amount of relief coupled with just the right saddle height.
  12. 96tbird

    96tbird PLEASE STAND BY Supporting Member

    OP thinks relief means banana. No it actually should run flat and begin to curve forward toward the head, not have a banana dip in the middle. If it looks like a banana, that's a ski jump neck and will need to be looked at by a pro.
  13. okcrum

    okcrum in your chest Supporting Member

    Oct 5, 2009
    Verde Valley, AZ
    RIP Dark Horse strings
    This is true for the fundamental. An EB puts out even more signal on the 1st harmonic, which is why you need a tad more relief than you'd think to get rid of fret buzz on the lower frets. Most of the bass' total output is in the fundamental plus the 1st harmonic combined.