I need help w/ my old bassman head

Discussion in 'Amps and Cabs [BG]' started by scorching5strin, Jun 5, 2004.

  1. scorching5strin


    Jun 5, 2004
    hello, i have a 1968 bassman head that keeps going through 6l6gc tubes like their going out of style. i've bought just about every brand of tube from musiciansfriend. if anyone could offer help as to what the problem may be i would greatfully appreciate it. thanks a bunch.
  2. g4string

    g4string Supporting Member

    Sep 19, 2002
    Melissa, TX
    Someone correct me if I am wrong, but shouldnt the amp be re-biased after a tube change?

    Another thought, buy matched sets when you re-tube. If you have 4 ea. 6L6's and 1 or 2 are blowing, replace all 4 as a matched set. All numbers used in that illustration were fictitious, but you get my point.
  3. There's an ongoing debate about whether the amp needs to be rebiased after every tube change. Ampeg V4's have fixed bias, for example, and they function adequately regardless of whatever 7027 you throw in there. Nevertheless, I understand the thought process behind checking the bias after a tube change.

    In this case, though, something is causing the tubes to die prematurely. The tubes should last for years and years. Yes, the bias may be wayyyyyy off, or some other component may have gone south, since this is an old amp. Electrolytic capacitors, such as the filter capacitors, are a prime candidate.

    Have the amp serviced by a good tube amp tech (in other words, don't take it to the bozoes at the local guitar center). The amp is a classic, so it's worth paying a few dollars to get it back in order--besides, you'll save that in tubes!!

    And for what it's worth, you can save money on tubes and get better products by ordering them from places such as Parts Express www.partsexpress.com or Triode Electronics http://store.yahoo.com/triodeel/index.html
  4. i agree on all that! my old bassman blew capacitors after changing tubes(i had it biased) but after having it biased again and changing the capacitors it worked just fine. i don´t know what the guy did with it but he said something about the voltage being set too high
    good luck it´s a good amp and i miss "mine"(loan)