'64 Blackface Super...with a mystery modification?

Discussion in 'Amp Central Station' started by hankseiz, Mar 23, 2004.

  1. hankseiz

    hankseiz Tele-Meister

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    Friend has a old, ugly, beat to hell '64 Super he's going to give to me for a couple hundred...a thousand cigarette burns on top, grill cloth is all smoke stained and nasty looking. Black covering all ripped & dinged from thousand of equipment vans. Still rocks tho'. It's got a plate screwed on the front claming it's been modded but he claims he doesn't know what was done.

    I looked around back and the only obvious thing I can see is that the GZ tube is plumb GONE! Yet the thing still rocks, sounds great. Do any of you tech guys out there know what could have been done which would have involved removing that tube? Was it a good thing or a bad thing? Any help appreciated. Thanks & kind regards, Hank
     
  2. Pierce

    Pierce Tele-Holic

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    solid state diodes

    soldered to the tube socket inside...was an early mod to increase headroom. If you slide the chassis out an ich you could see it..probaly everything is till attached for it to run with a rectifier if those are removed..
    if you haven't worked on amp before safety rules apply..enough lethal voltage thereto atleast make you p*** your pants
     
  3. Big Cookie

    Big Cookie RIP

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    I'd bet my money with the Gent from Skull Island

    Yepper I would lay my dough that it is a SS rectifier mod.
     
  4. jjmantele

    jjmantele Tele-Holic

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    Mod

    This mod results in higher voltage to the tubes. That means a little more potential volume, and more headroom. Also more "attack" since the diodes maintain a more constant voltage when more current is drawn thru them. No "sag" and less load on the power tranny since it doesn't have to supply the 5vdc to the (tube) rectifier heater. You can buy SS rectifiers that plug into this socket (when not modded) as an alternative to a normal tube rectifier. You can now also buy these gizmos that include built in resistors so the SS plug in "sags" like a tube rectifier would. Benefit is less stress on the power tranny and much more long term stability and life. They are called "Copper Caps" I think and are sold by Ted Weber on Webervst.com.

    Note that when you use a basic plug in SS rectifier the voltage increase (compared to the tube rectifier) means that you should adjust the bias to bring the output tubes' idle back down.

    If your a blues type guy I would have the mod reversed. You could always buy a $10 plug in SS unit to go back to the current sound as an option.
     
  5. Tim Swartz

    Tim Swartz Friend of Leo's

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    The first thing I check when I see that a SS rectifier has been installed is whether the PT is original. I've seen several that had replacements sans the 5V tap (ala Twin Reverb)
    .
     
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