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Acoustic bass head problem

Discussion in 'Amps and Cabs [BG]' started by dittohead, Sep 26, 2003.


  1. dittohead

    dittohead

    Sep 26, 2003
    I have an Acoustic Collaberation Series Tube 60
    bass head that barely puts out any volume,Power
    tubes were ck. ok.It was suggested Output power
    transformer might be bad.If someone has a wiring
    diagram for this head or any suggestions to diagnose and fix please email me at arkbluj@hot
    mail.com.thanks
     
  2. If it makes any volume at all, the transformer is OK. (it's either good or bad, it doesn't go "weak")

    More likely reasons:
    1) one or more filter capacitor has detiorated, usually accompanied by a hum. Very common problem with old amps as the electrolytic capacitors age.
    2) coupling capacitor going/gone. I had this problem myself with my old Ampeg.
    3) one of the resistors on the power tubes has burnt out. (fairly common)
    4) oxidation on input/output jacks or tube sockets (common, but usually accompanied by loud crackling when plug is wiggled)
    5) oxidation on potentiometer (commone, but accompanied by loud crackling when knob is turned)
    6) tube burnt out--not as likely as people think)

    Psycho Bass Guy is best resource to help you out. With a good schematic, a good meter, and some basic troubleshooting ability, a tech out to be able to isolate problem very quickly.
     
  3. dittohead

    dittohead

    Sep 26, 2003
    How do I contact Psycho Bass Guy?Thanks for the info
     
  4. I think he posted a response on a thread last night, or maybe night before. Hopefully he'll see this thread and respond, if not look for him (do a search for psycho) on this forum and PM him. I think he's out of Knoxville TN.
     
  5. Could be a whole slew of things, like nashvillebill said. To add to that, OT's can intermittantly short, but that usually toasts the output tubes. The best thing to do is let someone who knows what they're doing open it up and troubleshoot it. Without a WHOLE LOT more info, I can only give you help in the most vague sense.
     
  6. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    Is the driver tube OK?

    Also, does it have an output jack configuration like a Fender?...the main speaker jack is a shorting type to protect the OT if it is turned on without a speaker connected? If you're using the wrong speaker jack, this would be a likely symptom...

    Check to make sure that the jacks are clean too.