Untouched Original ‘67 Bassman AB165

Discussion in 'Shock Brother's DIY Amps' started by Skish, Feb 9, 2020.

  1. Skish

    Skish TDPRI Member

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    Just had a friend bring me an amp he picked up recently to have a look. Said it didn’t sound great. I’ve built a few Tweed clones and repaired some solid state amps. But I was pretty excited and a little shocked to see a completely untouched AB165 Bassman. I haven’t plugged it in yet, I immediately ordered a set of Electrolytic caps and a new matched pair of 6L6s. (Current powers tubes are different brand and style). While waiting for the caps, I was looking it over and noticed “warts” on the current caps. Are these normal or are they breaking down? Anyone seen these before?
    ADAC9FDD-24E6-4EEE-BE41-AC1628CF906D.jpeg
     
  2. David Barnett

    David Barnett Doctor of Teleocity

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    The "warts" are completely normal, for a capacitor that is failing. That's the electrolyte getting ready to spew its guts all over the inside of the amp.
     
  3. Ten Over

    Ten Over Tele-Meister

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    I surely would love to see some more pictures.
     
  4. Skish

    Skish TDPRI Member

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    Thanks David. That’s what I suspected. I hadn’t seen these old caps before so I wasn’t 100% sure. I figured it was dangerous to plug them although it has been played recently by someone else.
     
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  5. Skish

    Skish TDPRI Member

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    Sure...just some of the insides for now. I’ll have the caps in a couple days and get it reassembled. I washed up the tolex, it had a few years of grunge.
    I need to pickup the cab and give that a look too. Only have the head right now.
     

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  6. AlbertaGriff

    AlbertaGriff Tele-Afflicted

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    The only filter cap I've ever blown up was one of those in a '67 Bassman.
     
  7. jguitarman

    jguitarman Tele-Afflicted Silver Supporter

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    It'll be interesting to see if it has the original speakers or replacements. These are great amps but don't get the love they deserve because of the large speaker cab. I put a brown face Bandmaster head in a custom blond cab with a 15" speaker to make it gigable. Both the Bassman and Bandmaster amps can be bought for relatively little money and are wonderful vintage amps.
     
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  8. David Barnett

    David Barnett Doctor of Teleocity

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    "IP" for a date code seems unlikely, that would be the 16th month of 1959...

    If that were reversed, it would be 9th month of 1966, which seem plausible. Did they ever do the date code letters backwards?
     
  9. jguitarman

    jguitarman Tele-Afflicted Silver Supporter

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    Can't say that I ever saw backwards date codes but they sometimes put the wrong tube chart on the wrong amps so I'd bet it was a mistake. CBS even produced some early Bandmasters with the word Columbia misspelled before they realized the error.
     
  10. Skish

    Skish TDPRI Member

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    I think the part of the date code that looks like an I is the left edge of the stamp. And the second letter is actually very light and cutoff. It looks like possibly a “C”.
     
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  11. Skish

    Skish TDPRI Member

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    Can’t believe I hadn’t looked up these date codes on the tube chart before. So this is apparently a 66 not 67.
     
  12. David Barnett

    David Barnett Doctor of Teleocity

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    Good spot.
     
  13. Paul G.

    Paul G. Friend of Leo's

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    Is the faceplate silver or black? If silver, are there black lines between the channels?
     
  14. Paul G.

    Paul G. Friend of Leo's

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    Those electrolytics on the board should probably be replaced as well. Get five 25uf/25V electrolytics and change 'em. Those 3 big cardboard-looking things -- two of em are dual caps, but just replace them with regular singles.

    Do you know how to discharge caps and check? If not, you need to take the time to learn.
     
  15. corliss1

    corliss1 Friend of Leo's Platinum Supporter

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    And now you've seen what every vintage Fender looks like with caps that are long past their sell-by date :D
     
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  16. Skish

    Skish TDPRI Member

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    It’s a blackface. I’ll post more phots soon.

    I did order caps for the inside as well. Mostly F&T. They had dual caps so I ordered those to keep it the same.
     
  17. Skish

    Skish TDPRI Member

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    I should mention, I also order 1W metal oxide power resistors to replace those as well. I’ve often seen those included in the cap kits and assumed it should just be part of the job.
     
  18. Wally

    Wally Telefied Ad Free Member

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    The SF cosmetics did not begin until April, 1967.

    plus one on the date code being either PC or PG....PG being March, ‘67 and PG being July of ‘67.
    Nice amp....if he is lucky, there are Jensen C12N’s in that cab. If the speakers are 12T6 Oxfords, they are low efficiency speakers....and that might be a good thing if the owner wants to push the amp without blowing out windows.
     
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  19. David Barnett

    David Barnett Doctor of Teleocity

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    Were they still fitting Utah speakers in Bassmans at that time too?
     
  20. Ten Over

    Ten Over Tele-Meister

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    Thanks. I appreciate it.

    This amp is almost certainly a 1966, probably in March. "P" on the tube chart is 1966 and there is a date code on a capacitor from the 48th week of 1965.
     
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