Using magnets to effectively raise pole pieces?

Discussion in 'Pickups & Electronics [BG]' started by bassbuddy, Dec 22, 2017.


  1. My Sire V7 five string has noticeably diminished output on the middle A string due to the bass's setup. I don't believe that I can "push" the pole pieces up without damaging the pickup, and I've heard of folks effectively extending the pole pieces by adding small neodymium disk magnets to their top. Who can talk to me about this? Does it change the tone? Do they stay put? What size are you using, and where do you get them (although there are plenty of dealers on eBay). Thanks in advance for your input.
     
  2. Killed_by_Death

    Killed_by_Death Snaggletooth Inactive

    If you can see the pole pieces on the back you can push them forward:

    Nordstrand_Pickups_NJ5F_back_Jazz_Bass_400x.jpg
     
    gebass6 likes this.
  3. Double check that the A is also quiet with the bass unplugged, acoustically in a quiet room. It might just be a dude string.

    But yeah man, if you want to tweak the mags, then there's several approaches.

    If you decide to push the mags from underneath, here's how I do it:

    First, measure and record the heights of the strings above the pole pieces, so you can re-install them quickly at, or very near, their original adjustments. Also, leave your amp set at the same level. This will give your ears a fair chance of judging the success of your mod.

    Anyway, first I remove the cover and have a good look at the pickup. If it is neatly wrapped and wax potted, you have a good chance of moving the magnet without harming the coil. Some asian pickups are wound on to a bobbin that is formed with plastic holes for the magnets and the winding wire doesn't touch them at all, so you can shove those mags around as much as you like and you'd be very unlucky to damage the pickup. OTOH, most old fender pickups have the wire directly wound on to the mags, insulated only with a spray of lacquer. If you try to move the pole pieces, you will almost certainly kill the pickup. Especially the outer two pole pieces.

    OK, if it looks safe to move the mags, I lay the pickup upside down on my bench, resting on a couple of timber or plastic shims, the thickness of course, is the same amount I want to raise the mags. That way, they'll hit the bench at the right heights. This amount should be no more than two-thirds the thickness of the bobbin material. Use a pair of calipers to measure! Accidentally pushing the mag right through and past the lower bobbin material will most likely ruin the pickup.

    Try just pushing them with a screwdriver or a dowel or something. If they don't budge easily, apply a small amount of heat with a soldering iron. Heating the bottom and testing the top with your finger is the trick. It should be just warm and no hotter.

    If it looks like pushing them may harm the coil, then try adding a couple of neo cylinders underneath first. Buy some that are the same diameter as the pole pieces, and say, 3-5mm in length. Even little neos like these may recharge/reverse the alnicos if you force like-poles together, so be sure to orientate them correctly. (Use a compass to check them if you like.) They should just stay there, but you could put a tiny drop of super glue so they don't get dislodged with the foam or something. Also make sure the the route is deep enough. Puting them underneath is a nicer solution aesthetically, and may be all the pickups need- a little booost in magnetic strength at the A string.

    If you decide to add height to the polepieces, here's a sneaky trick that actually works. I've used it on stingray pickups to boost the G string a few times. Get some thin fridge magnet material - that sort of hard rubber, usually 0.5 - 1mm thick. Tradesmen often print their business cards on it. You can cut perfect circles with a leather hole-punch. Then simply place these on top (orientated correctly) with a tiny drop of super glue. This won't make the magnets really any stronger, but serves to raise the field closer to the string. If that dark brown colour looks out of place, perhaps a drop of silver paint or nail polish would work...
     
    tallboybass, Domespeed and Jim C like this.
  4. Jim C

    Jim C I believe in the trilogy; Fender, Stingray, + G&L Supporting Member

    Nov 29, 2008
    Bethesda, MD
    Did this fix the low output on the Stingray G string?
     
  5. Seeing as I am neither Lewis nor Clark, how does one do this? My experience with magnet orientation pretty much begins and ends with the little plastic Westie and Scottie I had as a kid.
     
    Last edited: Dec 23, 2017
  6. Killed_by_Death

    Killed_by_Death Snaggletooth Inactive

    If you start moving the magnet toward the pole piece & it attracts it, you're golden.
    If it repels it, don't force it, instead flip it.
     
  7. 96tbird

    96tbird PLEASE STAND BY

    Meh, it’ll flip itself. News are really string mags and it’s imposduvle to get even a little one close to another magnet without it flipping itself over. There is no danger of getting it backwards.

    Op will know immediately soon as he moves it within a few mm.
     
  8. Yahboy

    Yahboy

    May 21, 2008
    The Raw testing and it work !!!

    IMG_20160301_223326.jpg IMG_20160301_223409.jpg

    Later i buy few different size Neo Magnet .

    IMG_20160315_014157.jpg IMG_20160315_014224.jpg
     
    kodiakblair likes this.
  9. Yahboy

    Yahboy

    May 21, 2008
    If you have balls, you can do this like what i done with my previous Squier CV50P's pickup. Pop the A and D pole out a bit than fine tune it.

    IMG_20170404_010202_HDR.jpg IMG_20170404_102038_HDR.jpg
     
  10. Yahboy, those photos were the impetus for the thread. I ceartainly have the balls to pop my pole pieces, but given I’m happy with the current setup and I’m one of those guys that changes my strings MAYBE every five years per bass, I’m much more inclined to try a few small magnets as opposed to deconstructing my instrument. I have a few coming from eBay, so I’ll give it a shot and see what happens.

    The screws are hysterical.
     
  11. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

     
    May 25, 2022

Share This Page