Double-stop fret buzz

Discussion in 'Hardware, Setup & Repair [BG]' started by MTBassMania, Oct 25, 2017.

  1. MTBassMania


    Mar 5, 2013
    Curious thing just happened to me... Playing a groove that has a double stop on the 7th fret, 1st and 4th string. I hit it, and I'm getting really bad fret buzz on the G-string. I try hitting both notes in sequence - no buzz. The only time I get buzz is when I press both strings down. I even tried the double-stop, got the buzz, and lifted my finger off the E-string, and the buzz stopped - put it back on, and it starts again. I even tried hitting just the D on the G-string with my finger in the quirky position it needs to be in to perform the double-stop, and no buzz.

    Anyone ever have this happen before? It's almost like putting pressure on the E-side of the 7th fret is causing the G-side of the 8th fret to rise. It happens on the 6th fret, too. It only happens when both notes are on the same fret, tho.
  2. Turnaround

    Turnaround Commercial User

    May 6, 2004
    Toronto Canada
    Independent Instrument Technician
    Pretty common- a lot more common than you might think. Here's what's happening...
    When you fret the first and fourth string at the seventh fret, the note on the G string is D. Now while fretting the 4th string at the seventh fret, pluck the string between the nut and the where you are fingering. The string will buzz a bit, but the note you hear is also a D. The D note on the G string is setting up a sympathetic vibration on the E string behind where you are fretting it - which is also a D. Three ways to mitigate this problem.

    1. Mute the E string behind the 7th fret. Use your second and fourth finger to fret the notes, and use your first to damp the E string behind your second finger.
    2. Add a bit more relief. The additional relief may be enough to keep the string from rattling against the frets when it vibrates sympathetically
    3. Shim the E string nut slot (or a new nut with slightly higher slot for the E string).

    Even a well-designed and set up bass can run into this problem. Solutions 2 or 3 may not really help much if the bass is resonant enough to set up a strong sympathetic vibration. So really, as much as it is a pain in the butt, the first option is often the best.
    Dabndug likes this.
  3. Dabndug

    Dabndug Supporting Member

    Sep 27, 2017
    Somewhere in Oz
    Option 1 above is the "classical" way to play 10ths (minor or major) - second finger fretting the root on the E string with the first finger behind it, and fourth finger fretting the 10th on the G string, with the third finger behind it. It's a more comfortable position with major 10ths, but you get used to it pretty quickly with minor 10ths if you practice enough.

    When you start out playing 10ths, you're likely to get a little rattle beyond sympathetic string vibrations just because it's harder to fret both notes than you're used to, due to both the extra pressure involved in fretting two strings and the unfamiliar (and possibly slightly contorted) position of your fretting hand. You will iron this out over time.
  4. joebar


    Jan 10, 2010
    I've had this happen too but more commonly with certain tritones.
    Sometimes it's as simple as detuning the string and retuning it back up. I've had phantom rattles disappear this way.
  5. vin97

    vin97 Inactive

    Mar 7, 2016
    it's only acoustic, though right?
  6. walterw

    walterw Supportive Fender Commercial User

    Feb 20, 2009
    yep, like @Turnaround i knew what it was before even opening the thread!

    it’s the dreaded “backbuzz” happening between the fretted E and the nut.

    the trick is to lay a finger behind the fretting finger on the E.