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Just how should a Blend control sound?

Discussion in 'Pickups & Electronics [BG]' started by Hambone, Jul 5, 2004.


  1. My just finished project has an EB-3 Bridge pup in the neck position and Ceramic MM in the bridge spot. Passive controls are Volume, Blend, Tone. Volume and tone work like I would expect. But the Blend doesn't maintain the volume of the pickup as you move away from it and towards the other. Each pup is at it's max volume and tone on it's side of the sweep.

    Is this what a passive blend should do?
     
  2. Trevorus

    Trevorus

    Oct 18, 2002
    Urbana, IL
    Well, which pickup seems louder? I probably just has more output than the other one. Switching around bridge and neck pickups will do that sometimes.
     
  3. It's not a matter of max volume between the two pups. The problem is that as you pan from one pup to the other (either way) the volume drops off exceptionally as you pan away from full sweep to the center detente then increases as you pan up towards the other pup.
     
  4. Lockout

    Lockout

    Dec 24, 2002
    Illinois
    That doesn't seem quite right... I'm not sure what could be wrong, though. :(
     
  5. Trevorus

    Trevorus

    Oct 18, 2002
    Urbana, IL
    I'd say check the wiring. I usually wire it like 2 separate volumes that work opposite of each other.
     
  6. I had the same issue. The bass actually gets louder away from the center of the blend. I tried reversing polarity of one pickup, etc., but that didn't help. I'd be interested in the answer, also.
     
  7. I figured the opposite would be the case. It would get softer with one pickup on full.
     
  8. Do you have the pups wired properly? It sounds like they might be out of phase, so that they cancel each other out at the centre.

    But if your problem is the same as Katonart's, I can't help you because the solution to phasing problems is to switch one pup's wiring around.

    Josh D
     
  9. xyllion

    xyllion Commercial User

    Jan 14, 2003
    San Jose, CA, USA
    Owner, Looperlative Audio Products
    Hambone, try reversing the polarity of one of the pups and see if that helps.
     

  10. Wiring is correct. Switching polarity creates full Volume at center detente for that pup. Not what we want. Here's the link for the schematic:

    http://guitarelectronics.zoovy.com/product/WDUJBASS1

    IF a passive pan control is simply a pair of volume pots backed up to each other and with reversed paths to have one full on when the other is full off, then this thing IS working correctly. I think I fooled myself into thinking that there would be more signal from the opposite pup on each side of the detente.

    It might just take some getting used to.
     
  11. xyllion

    xyllion Commercial User

    Jan 14, 2003
    San Jose, CA, USA
    Owner, Looperlative Audio Products
    Did you specifically buy a blend pot? Blend pots also have a special tapering to them.

    From what I remember of blend pot behavior (I prefer volume-volume), the side being turned down generally falls off fairly sharply.
     
  12. Reversing the polarity shouldn't create full volume for that pup at centre detent. If the polarities are reversed, what is common to both sources will be removed (adding of waves).

    Most passive blends shouldn't actually be two volumes mounted backwards, somebody tried to explain it to me but I didn't really understand without a drawing, but the volume drop at the centre shouldn't be real noticable. All I've had experience with is passive blends and I've never noticed much of a drop at the centre, slight drop in some highs kinda (could be just me) but not a noticable drop in volume.

    Josh D
     
  13. geshel

    geshel

    Oct 2, 2001
    Seattle
    What resistance is the blend pot? That might be the behavior I'd expect if it was 25k/25k or something (which is too low for passive pups).
     
  14. That would be a good point to look for. This pot is a 500k just like the other two in the system. It is a real blend pot as described here:

    http://guitarelectronics.zoovy.com/category/20electronicparts.2controlpots. Mines the CPB500.
     
  15. maurilio

    maurilio Musician - Owner at Mo's Shop - Tech at Nordstrand Supporting Member

    May 25, 2003
    Studio City+Redlands, CA
    Endorsing artist: Nordstrand - Genzler Amplification - Sadowsky - Dunlops Strings - DR Strings
    Hey,
    I had the same problem, a while ago. I discussed the problem with Carey (Nordstrand) and he told me to change the pot. Some brand have a weird behavior... just my experience!

    Peace

    Mo`
     
  16. This is a high quality ALPS pot designed for the job. I'm getting used to it's sound now. I think the main difference between this setup and any other balance I've owned is that

    1. Both pups aren't the same - not even remotely
    2. They have different outputs - close but not matched
    3. They have radically different tones
    4. The system is passive - some loss of signal has to occur.
    5. The pups are spaced rather widely so timbre difference will be maximal

    Thanx for the help folks!!

    :D