1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  
     
    TalkBass.com has been uniting the low end since 1998.  Join us! :)

800RB Effects Loop Problem With a Twist

Discussion in 'Amps and Cabs [BG]' started by billinbrasil, Oct 30, 2017.


  1. This is my first post here, hello to all.

    After a 15 year hiatus, around two months ago I shook the dust (and humidity) off my bass rig. I had to replace the active circuit board on one of my basses and the dust caps have fallen off the speakers of my 410 Hartke cabinet. All in all however, things were much better than I expected. Except for one small problem that's got be baffled....

    Reading through threads here, I have learned all about the infamous "effects loop return jack issue". However, mine seems to be a touch different than the usual distortion and output variation when the jacks are not connected.


    What I got is:

    Nothing plugged into the effects loop ====>> zero output, nothing at all
    A patch cable directly from send to return ====>> normal function
    Compressor and chorus daisy chained through the effects loop ====>> distortion and output variation

    I tried cleaning the jacks with fine sandpapar but no change.
    What gives??


    TIA
     
  2. Try some Deoxit.
    If that still doesn't do it, maybe new jacks are in order.
     
  3. Well, I think you need to make sure the symptoms in example 3 above are not the compressor and/or chorus themselves. Either test them on another rig using a send/return loop, or, place them in line BEFORE your amp, and of course, use a patch cable from the amps send/return jacks to connect those together, like you did in your second example.

    Start there and report back.
     
  4. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Sanding your jacks pretty much ruined them as a starter... why?
     
    BassmanPaul likes this.
  5. I'm thinking some bad info passed along via the internet........
     
    agedhorse likes this.
  6. It’s not the tip and sleeve contacts that are the problem but the switches built into the socket that cause the problems.
     
    walterw likes this.
  7. It´s not the compressor or chorus, these work just fine in-line before the amp input. I´ll be replacing the jacks this weekend and be done with this.

    About that......

    The only advantage that I can see with having a switchable jack is so that the signal gets through when no cables are connected. However, there´s the downside of more likely jack failure. Would there be any reason to not just use regular jacks and connect a cable between them when running the amp without effects??
     
  8. ....and about the sanding of the jacks.... Considering that an engineer from Mesa Boogie is telling me that it's a no-no, I guess I'll accept that it's a no-no. However, I must say that I've done this on an untold number of occassions and it has most always been helpful.

    We're talking about light sanding with fine sandpaper....
     
  9. walterw

    walterw Supportive Fender Gold Supporting Member Commercial User

    Feb 20, 2009
    alpha-music.com
    just the hassle of the extra cable.

    as it is, you can just do that until you get the switching jack fixed in the amp.
     
  10. Thanks for the input, guys!!
     
  11. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    There's a reason we pay for jacks with fine plating on the contact surfaces... until it's sanded off ;)
     
  12. Inserting a cable to do the temporary fix IS the normal condition when the switching contacts fuzz over.
     
  13. Your pedals don't deal with the high signal level of the loop.
     
  14. petrus61

    petrus61 Supporting Member

    I've found pots inside of bass cavities that it looked like someone took a belt sander to, probably not aware that those also have a special surface that doesn't require any sandpaper.
     
    agedhorse likes this.
  15. TBGFRED

    TBGFRED Supporting Member

    Apr 24, 2009
    Panama City Beach, FL
    ok, i'll be the one who admits he doesn't know - how does this ruin them? i might have intuited that if a light haze of corrosion had formed and was interfering with connection, a light burnishing would remove... ? i recalled we once used pencil erasers to brighten the contacts and brushes on our slot car motors...

    please coach us up!
     
    kap'n kro likes this.
  16. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    The contact surfaces are generally plated with a few ten-thousandths of an inch of nickel or in some cases nickel-silver (NiAg). There is generally not a corrosion problem, but a microns thick oxide or contaminate film. Sanding is like hunting fleas with a 50 cal.
     
    JMacBass65, kap'n kro and TBGFRED like this.
  17. BTW, as my compressor and chorus are rack mounted effects, I've always just "naturally" run them through the effects loop. However, I'm liking the sound I'm getting with them in-line with the bass.....
     
  18. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Which compressor and chorus are you using? Some are switchable between instrument and line level. If a switch got changed by accident, this could cause you problems.
     
    JMacBass65 likes this.
  19. An Ink rubber/eraser would have been equally effective but would leave the plating intact.
     
    JMacBass65 likes this.
  20. I´m using and old Behringer compressor and an even older Art Multi-Effect unit. Not the best stuff but for my purposes they work fine....
     

Share This Page