JCM800 Bright cap ,......which one is it ,.. anyone did a clip job ?

Discussion in 'Marshall Amps' started by Kelia, Mar 29, 2020.

  1. Kelia

    Kelia Well-Known Member

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    Hi guys ,.....my JCM800 doesn't have that ice picky awfull sound on lower volumes that I've heard on other amps including late JMP's but I've also read that clipping it makes the amp sound rounder and more pedal friendly ,..some guys put it back in so the best way for me
    is to clip it and see if I like it more but the problem is that there's three of them
    and I don't know whcih one to clip ?

    Anyone hear playing witout it ?

    Thanks !

    [​IMG]
     
  2. Matthews Guitars

    Matthews Guitars Well-Known Member

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    It's the one on the back of the volume control, not the one strapped across the resistor.

    Rather than clip it, unsolder one lead and let it hang free. You can then just resolder it if you liked it better as it was.
     
  3. ampmadscientist

    ampmadscientist Well-Known Member

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    Brightcap.png
     
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  4. Kelia

    Kelia Well-Known Member

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    Wow !,......Ask and you shall receive !!........Thanks guys,....appreciate !
    Will try this.
     
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  5. Seanxk

    Seanxk Well-Known Member

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    Turn your Pot to full or off, not good if volume is at 5 and you heat the centre lug as it can heat through to the brush and burn the track.
     
  6. MarshallDog

    MarshallDog Well-Known Member Premium Member

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    If it does not sound ice picky then leave it. Having no cap at all will make it sound dead. Ive done it on this exact amp but mine was ice picky to start with. I believe I ended up with a 480 or 560 pF in that spot.
     
  7. Jethro Rocker

    Jethro Rocker Well-Known Member Premium Member

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    What about the one strapped across the resistor? Just curious. It's some sort of treble cap, no?
     
  8. MarshallDog

    MarshallDog Well-Known Member Premium Member

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    I believe thats called the first stage treble peaker. Ive played with that arrangement also and in the end went back to stock.
     
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  9. MarshallDog

    MarshallDog Well-Known Member Premium Member

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    Are you trying to make it sound brighter or less brighter?
     
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  10. Jethro Rocker

    Jethro Rocker Well-Known Member Premium Member

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    I assume he wants less bright. I wondered about that too but wasn't sure what the treble peaker did
     
  11. MarshallDog

    MarshallDog Well-Known Member Premium Member

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    If its not ice picky now I’ll bet a pack of TP on it that he wont like it at all with nothing there. 0 pF there makes an amp sound dead IMO and I dont like ice picky at all. I guess he should give it a try if he can solder!?
     
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  12. Jethro Rocker

    Jethro Rocker Well-Known Member Premium Member

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    What does the treble peaker do then? Just curious, I mean I do like how my 4010 cuts. Partly what makes an 800 an 800. Single channel that is. If ice picky can kill some presence I guess
     
  13. MarshallDog

    MarshallDog Well-Known Member Premium Member

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    I guess it just adds some treble response early on in the amplification process!
     
  14. coolidge56

    coolidge56 Well-Known Member

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    Trying to fix a problem that does not exist frequently leads to trouble. A cut finger, you poke out an eye, etc.
     
  15. Kelia

    Kelia Well-Known Member

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    I just tried it and it sounded like a cranked 1986 without the 800 growl so I put it back in
    and it will stay there ,.it's not ice picky ,........I was just curious and needed to try it.
    Think it's one of the best amp I ever played !.........when I play it ,I hear about every Classic Rock records done in the 80's !
     
  16. Kelia

    Kelia Well-Known Member

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    Thanks for the input ,............didn't know that .
     
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  17. wakjob

    wakjob Well-Known Member

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    I've said my peace on the brite-cap issue enough...but, I like it stock mainly for the way it helps with reaction to the guitars volume control.

    I modded my 2204 to the moon and back.
    In the end, near stock with just some component upgrades, and it was at its best.
     
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  18. Kelia

    Kelia Well-Known Member

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    Curious on what components upgrade you did ?
     
    Last edited: Mar 29, 2020
  19. wakjob

    wakjob Well-Known Member

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    The aforementioned UF4007's.
    And Sozo's replaced all the Wima's.

    That, along with some choice tubes and I was done with it.
    I learned that a 2204 wants to be a 2204...and nothing else.
     
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  20. Kelia

    Kelia Well-Known Member

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    Thanks wakjob !..........the UF4007's makes the amô feel spongier or what exactly does it do ?
     

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