When you cant find the right multi cap??

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by jr_vw2, Sep 16, 2008.

  1. jr_vw2

    jr_vw2 Member

    Messages:
    71
    Joined:
    Jul 28, 2008
    Location:
    Chattanooga TN
    So what do you do when you cant find the right value multi section capacitor, and you have limited space so single caps are out of the question? I know VibroWorld makes custom caps but they are moving and not taking any orders. I am looking for 33uf/33uf/22uf above 450v I would settle for 30/30/20 but I cant find either. I really dont wany to use some no name of the wall brand either. I want quality parts. Any ideas?? Thanks
     
  2. SatelliteAmps

    SatelliteAmps Member

    Messages:
    6,185
    Joined:
    Oct 19, 2007
    Location:
    Normal Heights, Calif
    If you can't find one, you could use a JJ 40x20x20x20, and tie two of the 20's together, giving you a 40x40x20. They are rated for 500v.

    You can check at www.tubesandmore.com or www.newsensor.com

    Antique Electronic Supply has a lot of different multi section cans that might also work. Their site is down right now, but it should be up later today.
     
  3. jr_vw2

    jr_vw2 Member

    Messages:
    71
    Joined:
    Jul 28, 2008
    Location:
    Chattanooga TN
    what are the guidelines for values? How much can you stray from your disired capacitance?
     
  4. brad347

    brad347 Member

    Messages:
    4,813
    Joined:
    Feb 8, 2006
    Location:
    Brooklyn, NY
    general rule of thumb is doubling or halving causes a readily noticeable change in performance. When you consider that tolerances are often 20%, then that sort of puts it in perspective.

    40 40 20 would certainly be an acceptable replacement for 33 33 22 in my opinion.

    It might filter slightly more/better, but I doubt it would be noticeable. Any change you would notice would more likely be due to new caps versus old caps.
     
  5. SatelliteAmps

    SatelliteAmps Member

    Messages:
    6,185
    Joined:
    Oct 19, 2007
    Location:
    Normal Heights, Calif
    It might tighten up the bass a hair. The main issues can come up when an amp has a tube rectifier, as they have capacitance limits upon them. 40uf is within the range of most tube rectifiers used in guitar amplifiers. Should be perfectly fine.

    Just checked Antique Electronics, and they have a 30/30/30uf @ 525v that would also work fine.
     
  6. hasserl

    hasserl Member

    Messages:
    4,734
    Joined:
    Oct 24, 2004
    Location:
    So Cal
  7. mbratch

    mbratch Member

    Messages:
    2,390
    Joined:
    Nov 3, 2003
    Location:
    Webster, NY
    AES has a huge variety. Check here. For example, you can get the 80/40/30/20 and combine the 80+40 in series, which you would then have 27/30/20. Pretty close to the 30/30/20. :)
     
  8. rooster

    rooster Member

    Messages:
    2,123
    Joined:
    Mar 9, 2005
    Location:
    Arizona
    Um.. they have a common negative. You can't combine sections within a multicap in series, only in parallel.

    rooster.
     
  9. mbratch

    mbratch Member

    Messages:
    2,390
    Joined:
    Nov 3, 2003
    Location:
    Webster, NY
    Oh right... sorry 'bout that.

    Nonetheless, AES has enough variety to get him pretty close. :)
     
  10. jr_vw2

    jr_vw2 Member

    Messages:
    71
    Joined:
    Jul 28, 2008
    Location:
    Chattanooga TN
    Thanks for all the help guys
     

Share This Page