Pignose 7-100 fizz

Discussion in 'Amp Tech Center' started by Bluesman90, Jun 30, 2020 at 10:35 PM.

  1. Bluesman90

    Bluesman90 TDPRI Member

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    Hello friends! I recently purchased a Pignose 7-100 but I can't get good clean sounds as there is some fizz in the background. Is this normal in the Pignose?
    I am attaching a video where you can hear this fizz.

     
  2. galaxiex

    galaxiex Tele-Afflicted

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    Read this thread...

    https://www.ssguitar.com/index.php?topic=1166.0

    You may have to join (free) to see pics and such.

    Post #19 and on in the link above discusses the "fizzyness" of the Pignose.

    There is a design flaw in the circuit that you can remedy as discussed in the thread.
     
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  3. Bluesman90

    Bluesman90 TDPRI Member

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    That thread talks about the Pignose Hog 20 right? I have a fizz problem at 7-100.
     
  4. Jon Snell

    Jon Snell Tele-Meister

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    The Zobel components are not fitted to many. Fit a 0.47uF 100v capacitor and 2.2 Ohm resistor in series from pins 5 and 7 to ground.
    See schematic showing the correct Zobel network for the car radio amplifier TDA7240a; R1 & 2, C 5 & 7.
    Screenshot 2020-07-01 at 07.58.32.png
     
  5. galaxiex

    galaxiex Tele-Afflicted

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    Sorry :oops:

    My mistake.
     
  6. Jon Snell

    Jon Snell Tele-Meister

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    Fizz issue on 7 - 100 check R10 and D1.
     
  7. Pasta Player

    Pasta Player Tele-Meister Ad Free Member

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    Humbucker or single coil pups? Roll volume back a bit on the Pignose and maybe the guitar too to see if you can dial it out. If not… absolutely fresh batteries in? Tried wall plug power?

    Of all the Pignoses here (7-100’s /and there are quite a few) low power or less-than-fresh batteries can cause similar sound issues. Have also “upped” the voltage to 12 volts (and even 18 VDC) to alleviate this symptom, before delving into the more specific electronic bits.

    Try fresh batteries or the wall plug power. If no help and you don’t care to replace resistors, or chase other possible tiny electronics… unload the Pignose and find yourself an old Dwarf or Pygmy amp. I like the Pignose 7-100 and the novelty of having one working to the best of its’ abilities but the Dwarf and even the Pygmy amp - both put the Pignose 7-100 to shame.

    Group A.png
     
  8. Bluesman90

    Bluesman90 TDPRI Member

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    My Pignose 7-100 does not use an integrated circuit like the TDA7240a, only 4 transistors. Will I be able to do the Zobel network anyway?

    The recording was made with single coils. The Pignose was powered by T-Rex Fuel Tank Classic. It was also tested with batteries, same result.

    My idea is not to change the entire circuit, just get rid of the fizz. I love the classic Pignose sound
     
  9. soma89

    soma89 Tele-Meister

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    Owned 2 pignoses and they both had the annoying fizz in the background when it was clean. Their customer service was horrible and they pretty much said its a cheap amp so live with its imperfections. I sold both and never looked back.
     
  10. rangercaster

    rangercaster Poster Extraordinaire

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    Just sell it and buy another one ...
     
  11. Jon Snell

    Jon Snell Tele-Meister

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    Different schematic that has no use for a Zobel network.
    Check the bias as I explained in post 6.
    Have fun.
     
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  12. Javier668

    Javier668 TDPRI Member

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    Pignose isnt for cleans, the pig name is for dirt.
    My champ cranked have that little fizz too.
    If you want perfect cleans you need other amp.
    The tone is very fuzzy.
     
  13. LutherBurger

    LutherBurger Friend of Leo's

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    Yeah, I think it is. I was playing mine yesterday -- there are no clean sounds in that box. You just gotta embrace the dirt.
     
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