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Thread: Single coil magnetic 'strat' pickup problem uneven amplification

  1. #1

    Default Single coil magnetic 'strat' pickup problem uneven amplification

    Hi, new to the group but have read from it over the years. I'm more of a guitar player that wants an inexpensive serviceable mandolin that can be easily amplified. I have a cheap, no name mando that has a surprisingly good neck. Action is low, no buzzing notes, intonation pretty good, no complaints. The problem is the single coil pickup is amplifying the A strings twice as loud as all the others. Has anyone else ever heard of this before or any thoughts on what could be going on, or how to fix it? I always thought that was more of a piezo problem. A photo of the pickup is attached. Thanks for any insight.
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  2. #2
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    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    Since you don't have pole pieces and I am assuming you don't want to fiddle with an EQ. I would try copper shielding tape on top of the pickup, under just the A string. See if it tames it down, if it is too much use thinner strips. I haven't tried this, but trying to stop the string from driving the pickup with something is the only easy thing I can think of at the present.
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  3. #3
    Dave Sheets
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    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    Hmm, the A string probably has the thickest steel core of all the strings, since the A is unwound? Maybe try a different set of strings, with all steel or nickel wraps maybe?
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    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

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    i've spent the last hour and 1/2 raising and lowering pickups to try to even out output/tone, have you tried same, esp. lowering the treble side and relatively raising bass side? Would help to know if it's a blade, stacked humbuckr or s.t. else under the cover. Also possible it wouldn't be so bad run thru compressor/limiter
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  5. #5

    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    Depending on how much you want it to have similar qualities to an acoustic mandolin you could try restringing it with a custom set of electric guitar strings. It's likely the difference in metal content that is causing the difference in output. You might also try a set of Monel strings mandolin strings.

  6. #6

    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    I haven't pulled the pickguard up yet to examine the pickup under the cover, I assumed it's single coil but maybe not. I'll try the tape shielding idea first. I don't think lowering the treble side will work because the E strings are already so relatively weak. Thanks for the suggestions.

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    Registered User Tom Wright's Avatar
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    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    Quote Originally Posted by Rustoleum View Post
    I haven't pulled the pickguard up yet to examine the pickup under the cover, I assumed it's single coil but maybe not. I'll try the tape shielding idea first. I don't think lowering the treble side will work because the E strings are already so relatively weak. Thanks for the suggestions.
    We usually find some tilt, raising the treble and lowering the bass, is needed. But I’ve dealt with this style and you can improve it. If you get inside the pickguard you will probably find a single-coil design with a ceramic magnet underneath, along with alnico pole pieces. The underneath magnet means you can’t lower the A pole but the others can be pushed up. Pry off the ceramic magnet, tap the E pole upward with a wooden dowel and hammer. Re-attach the ceramic magnet and put everything together after drilling a hole to in the pickup cover allow the E pole to extend. Do not be afraid to push the E pole quite high — I would suggest about 3/16”.

    You may also want or need a ground wire which can run from the endpin to the output jack, wound under those washers.
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  8. #8

    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    "The underneath magnet means you can’t lower the A pole but the others can be pushed up."
    The push up pole pieces is interesting. Is there a gap/air between the poles and the ceramic magnet-they don't have to touch each other? I have to take it apart and check it out.

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    Registered User Tom Wright's Avatar
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    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    Quote Originally Posted by Rustoleum View Post
    "The underneath magnet means you canít lower the A pole but the others can be pushed up."
    The push up pole pieces is interesting. Is there a gap/air between the poles and the ceramic magnet-they don't have to touch each other? I have to take it apart and check it out.
    True, contact not necessary, itís magnetic fields, not electric current, and the pole piece itself is a magnet.

    Another approach is to just add an appropriate small piece of ferrous metal on top of the weak pole, like a small nut. But getting the pole closer will yield a larger effect.

    When I used one of this type of mando I used nickel-wound for D and G and the balance was OK except for the E. Pushing the pole piece closer gave me a good balance.
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    Default Re: Single coil magnetic 'strat' pickup problem uneven amplificat

    If you can take the pole piece out completely for the A string that will work as well. A guitar friend of mind takes the pole piece for the B string out of all his guitars and has great balance. He is open tuned in an open C tuning.
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