BF bassman heads how to tell which circuits they are

Discussion in 'Amps and Cabs' started by Seegs, Dec 27, 2009.

  1. Seegs

    Seegs Member

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    been looking at checking one of these out but how to tell...without opening them up...which circuit is inside...supposedly the AA864 is more desirable without modding...if you've played both which do you prefer

    got some 64s and 66s to check out...like to build it into a 1X12" combo...

    Chow,
    Seegs

    [SIZE=-1]AB165[/SIZE][SIZE=-1](1964-1983)[/SIZE] [SIZE=-1]AA864[/SIZE][SIZE=-1](1964-1967)[/SIZE]
     
  2. ispunk

    ispunk Supporting Member

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    The only way to know for sure is to open it up and look at the circuit. The tube chart does not always match what circuit is inside.
     
  3. twangbanger

    twangbanger Supporting Member

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    the only way is to open her up, Not hard to mod a AB 165 to the AA864. Not to many of the later ones out there and also most of the bassmans out there have been modded already so you need to look inside to see whats already been monkeyed with. Good luck!
     
  4. Seegs

    Seegs Member

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    ok thanx guys...not sure I'm gonna be able to open em up before buying...I'll have to ask and hope the sellers know which circuits they have...

    Chow,
    Seegs
     
  5. sickboy79

    sickboy79 Member

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    Yep - as said abover - gotta see that circuit board! Fender was notorious for using old "tube charts" until they ran out. A lot of times, you tube chart was one version behind!
     
  6. ispunk

    ispunk Supporting Member

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    One last note. Fender never made a tube chart for the AC568 (which is a goofy hybrid biasing circuit). If there's no tube chart that may be a sign of the AC568. I found this out the hard way.
     
  7. fishlog

    fishlog Member

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    Don't mod... They are all getting rare. And truth be told they all sound good.
     
  8. m@2

    m@2 Member

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    i agree!
     

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