CTS pickup blend pot with center-detent for Jazz control plate

Discussion in 'Pickups & Electronics [BG]' started by soaf, Dec 19, 2013.


  1. soaf

    soaf

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    I like the idea of a vol/blend/tone configuration rather than vol/vol/tone. There's something attractive about a notched pickup blend control. Are there any disadvantages? Is any tone sacraficed?
     
  2. line6man

    line6man

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    Blend pots are the equivalent of two volume pots, in a circuit, and thus, you decrease the total output impedance, reducing output and treble. This can be minimized by choosing higher value pots.

    Blend pots are also known to be problematic, as there is no easy way to passively mix pickups. Uneven blending and volume drops at the center detent are common, but the effect can be lessened with a good taper, and pickups of similar output impedance.
     
  3. soaf

    soaf

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    Ok, so if I do this, I will use 500k pots. What do you mean by a "good taper"? Don't most new pickups have similar output impedance when shipped as a pair? Thanks... I appreciate your expertise.
     
  4. line6man

    line6man

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    M/N taper is usually superior to A/C taper.

    It depends on the type of pickups. Jazz pickups are meant to blend well. Single coils and split coils, or humbuckers and single coils, or such, tend not to mix.
     
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  6. soaf

    soaf

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    Is a taper something that gets wired in? Is it a component?
     
  7. line6man

    line6man

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    Taper is the behavior of the pot as its resistance varies with position.

    For example:
    [​IMG]
     
  8. soaf

    soaf

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    So based on my two recent posts, I think you see I am trying to do a vol/blend/tone control plate for a jazz pass with passive pickups. From what you say, 500k pots would be better for this. Is this overall a bad idea? Should I just stay with v/v/t? The pain is having to fade out a song with separate volume knobs for each pickup.
     
  9. line6man

    line6man

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    If the bass has 250k pots, adding a 500k blend with a 250k master volume will keep things more-or-less the same. If the bass has 500k pots, a blend pot will make things darker. However, overall, the effect of pot values is subtle, and people tend to make too big of a deal about them. I wouldn't worry about it. Just choose the configuration that is practical to you, and pick the best components to do the job.
     
  10. soaf

    soaf

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    I will be building from scratch, so I guess 250vol/500blend/250tone would be suitable. I guess I will use an orange drop on the tone. Seems to be the standard preference. I know that could be a whole separate thread but any info would be helpful. There is one guy on a popular auction site selling a jazz setup with jack and CTS pots including centre-detent, unwired, all 250's or all 500's, so I may just stick with 500s for all three. Also comes with orange drop capacitor.
     
  11. line6man

    line6man

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    It doesn't matter what kind of capacitor you use, as long as it's non-polarized, and has a decent tolerance. Orange Drops are favored because they are commonplace, decently spec'd, and used to be inexpensive, but the price has gone up over the past few years.
     
  12. walterw

    walterw Supportive Fender Gold Supporting Member

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    line6man is spot-on (as usual); search "blend pot" on TB for tons of threads about these, and different ways to use them.
     
  13. andk5591

    andk5591

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    If you are like me - I need to be able to adjust the volume some, but its a hassle with the 2 volume controls. I just use 1 vol, 1 tone and a selector switch. I mean, how often do you adjust the blend?
     

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