Volume controls on Spector Legend 4

Discussion in 'Pickups & Electronics [BG]' started by Maz, Nov 8, 2012.


  1. Maz

    Maz

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    I have a newly aquired Spector Legend 4 I bought used and I have a problem with the volume controls. Starting from the "off" position on both volumes, the knob travels almost an 8th of a turn in silence, then the sound cuts in suddenly at a fraction of it's total volume. The volume rises gradually from that point, but not being able to fade in from silence is bugging me.

    An instrument of this grade shouldn't have shoddy electronics, so I took off the cover and had a peek. The top and left pots are the volumes. It looks like the original pots have been replaced with Alpha B500k pots. The solderjoints are messier than on the other two pots, so I'm convinced the previous owner tried to mod the bass.

    Can anyone with a spector legend out there tell me what pots I should have? I'm pretty disappointed in the sound quality of this bass in addition to the volume issue, and I hope changing the pots back to whatever they're supposed to be will fix it. Thanks in advance for any information anyone can help me out with.
     

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  2. Lemon Of Troy

    Lemon Of Troy Banned

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    What kind of pickups are in the bass?
     
  3. Maz

    Maz

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    EMGSSD (stock) passive EMG's
     
  4. Lemon Of Troy

    Lemon Of Troy Banned

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    Those values should be correct for passive pickups, so that's not the issue. I could be the taper of the pots....audio taper or linear taper, I forget which one is smoother. But one of them does nothing for most of it's range, then BAM! Everything is on. I think you need audio taper.
     
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  6. FunkMetalBass

    FunkMetalBass

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    I believe mine also had the linear 500K pots in it too, and I think that is also the stock wiring. There's a debate among bassists that linear tapers actually give a smoother taper since we don't often overdrive/distort as much, but you might try some audio pots (A500K) instead.

    FWIW, I use linear pots for all of my bass volumes.
     
  7. Maz

    Maz

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    I can't believe a bass in this price range would have volumes that don't come on smoothly. Thing is, it really isn't that big of a deal to me, but this bass just doesn't have the magic for me generally, and I'm thinking of unloading it. I don't want to sell it with defects though so i was hoping to find a solution to the volume problem. Maybe I'll switch to audio taper pots. and see how that works. Thanks for the input.
     
  8. jbrew73

    jbrew73

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    Look at the way the pots are wired and compare it to a jazz bass wiring diagram. The pickup leads should be wired to the wiper of the pots.
     
  9. Maz

    Maz

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    I Googled up a tonepump jr diagram and rewired the pots accordingly. No dice. I'm convinced those are audio taper pots, So i'll change them when I get a chance.
     
  10. Maz

    Maz

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    So I've done a little homework, (just enough to be dangerous), and I got ambitious with rewiring this bass. I never did switch to audio taper -they were in fact linear to start with, but I don't think that's the issue.

    I put in a 3 band pre, active/passive bypass, and Series/parallel switch. Here's the diagram:

    [​IMG]

    the bypass and series/parallel switches work fine, as does the preamp. I buzzed the ground through the pre and it's continuous, so I ran the ground from the s/p through the pre to the output, and it works. The pots are grounded to the case of the bypass/tone switch and out to sleeve from there.

    The problems:

    • The volumes still cut out at the bottom of their throw, not as severely as before though
    • The majority of the volume increase is in the top end of the throw
    • With either volume all the way up, the tone does nothing
    • The tone control has more effect on the sound the lower the volume is

    These pickups are listed as High Impedance, so they shouldn't take really low value pots right? -They were wired to 500k's to start with.

    I've also seen diagrams where the cap on the tone is wired from the wiper terminal to the ground and the signal is on the output terminal instead of the way I have it wired, which I thought was standard. Would rewiring the tone make a difference?

    I also didn't bridge the ground terminal on the bridge volume to its respective pot. Could that cause problems?

    :help:
     

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