Bridge Question

Discussion in 'Setup & Repair [DB]' started by dragonetti11, Aug 15, 2004.

  1. dragonetti11


    Jun 20, 2002
    I have an adjustable bridge and I am wondering if the height of the adjusters must be the same. The reason I ask is because I have noticed a big difference in the sound when the adjusters are at certain heights and one higher than the other might help me get the sound I want. They even get rid of a wolf note at a certain height. I heard once that it will put more pressure on one side but I am not sure.
  2. Well seeing how your strings aren't all the same thickness and that most necks have a bit of a curve to them rather than being flat, I don't think having the bridge saddles completely lined up at the same height even makes a lot of sense necessarily.
  3. There is no reason why the adjusters have to be exactly the same. In fact, being able to compensate for string height variations caused by humidity, temperature, etc. is the reason why we have adjustable doublebass bridges. Ofcourse there are practical limitations on how much they can differ, but generally a difference of up to 1/4" is safe on most well installed bridge adjusters. A large difference does put extra strain on the bridge. IMO, a bigger danger is having the exposed thread over half of the total length of the threaded portion of the adjusters. Most adjuster have thread lengths of around 3/4"
  4. dragonetti11


    Jun 20, 2002
    "In fact, being able to compensate for string height variations caused by humidity, temperature, etc. is the reason why we have adjustable doublebass bridges."

    Just checking to make sure you know what I am trying to say. I'm talking about the adjuster on the bass side being, for example, 1/4" up and the other, on the treble side being 1/8" up.
  5. I understood. 1/8" difference shouldn't be a problem. However, if it stays that way year round, you might consider getting a new bridge or at least having the present one recut to even out the height.
  6. dragonetti11


    Jun 20, 2002
    I'm not doing it for the height but rather for the sound. It's pretty amazing how much a difference it can make.
  7. Although you may not doing it for height, IMO it is the height that makes the difference in the sound - not the adjuster difference. A properly cut bridge without adjusters (at the same string height) would give you the same sound except possibly for the slight tone coloration that some adjusters add.
  8. arnoldschnitzer

    arnoldschnitzer AES Fine Instruments

    Feb 16, 2002
    Brewster, NY, USA
    I recommend to my clients they have no more than 1/2 turn difference between adjuster wheels. Any more can cause misalignment and stripping of the fragile wood threads. If the heights are so wrong that you need 1/8" difference, something is wrong. Keep in mind that if you only crank one side up, you are not raising that side but just moving the strings sideways in relation to the fingerboard. Perhaps it's the centering issue that's the problem with the tone.
  9. While I agree with Arnold that in a perfect world that 1/2 turn difference would be a nice ideal, the fact is that many players do routinely have differences of 1/8" to 1/4" due to changes in relative fingerboard height. In some cases, a better solution would be to change the soundpost with different lengths according to the seasonal changes. I've got a few clients who will go to the effort to change the post seasonally, but most do not. I've seen far too many players get away with this difference to believe that the theads of a properly installed bridge will fail (atleast on the ones I've seen around here) - Unless the threads are over 50% exposed resulting in less than 50% threaded surface area. IMO If adjusters are installed properly, those threads should not be that fragile.
  10. Jeff Bollbach

    Jeff Bollbach Jeff Bollbach Luthier, Inc.

    Dec 12, 2001
    freeport, ny
    I'd be less worried about stripping threads and more about cracking the leg. It the wheels are dead even and then one is cranked out a 1/4 in you are binding the ends of the adjuster shafts terribly in fragile endgrain. Can't be good for the tone-can certainly crack the leg. Bob, don't give me any B.S. about that not being much of a risk i have seen it many times. Arnold is right, if someone needs to have that much differential something is wrong elsewhere. I tell my peeps that if they can EASILY see a difference in the height than that is too much.
  11. No B.S. Jeff - I am not saying that nothing is wrong. I'm simply stating my opinion that the thread themselves will not fail if the adjusters have been properly installed. I agree with you about cracking the feet, and of course I've seen that happen. However, I've never seen the threads themselves fail if the adjusters were installed properly. The only ones I've observed fail were DIY projects that were done poorly. YMMV
  12. Jeff Bollbach

    Jeff Bollbach Jeff Bollbach Luthier, Inc.

    Dec 12, 2001
    freeport, ny
    sorry Bob, jes tryin' to yank your chain.
  13. I love it when you guys argue!
    I'm embarassed to ask this....What the hell does YMMV mean?
  14. Hey Paul - We don't argue. We just occationally have heated intellectual discussions. ;)

    YMMV = Your Mileage May Vary