Plexi Players: Anyone use Normal Input? (input II)

Discussion in 'Amps and Cabs' started by JubileeMan 2555, Feb 16, 2012.

  1. JubileeMan 2555

    JubileeMan 2555 Member

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    I sorta just discovered this input this week. Its always been there, but originally, I wanted to be a purist and just crank the amp to 10. for this purpose, the higher treble response of input 1 (I don't have a bright cap installed...btw) was better for the cranked tone.

    BUT, now I use a pedal as my main overdrive and put it into the normal input and keep the volume around 5/6. I found this to be MUCH MUCH more musical sounding.

    The only difference between the two inputs is the mixer bypass cap (560pf) and I'm rather shocked how much that little cap seems to add nasty sounds to the guitar signal.

    Research has shown it to be a sort of EQ boost at roughly 1K and I think thats a harsh frequency to focus your guitar around. Then, when plugged into the normal input, the bright volume pot then seems to act as a 1K boost knob since with the volume off, I think the circuit is then bleeding the 1K resonence to ground. Turning up the pot lessens that effect. Its very complex!

    I'm still experimenting, but I seem to find this normal input to be far musical in general.
     
  2. ufguy73

    ufguy73 Gold Supporting Member

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  3. ScottR

    ScottR Silver Supporting Member

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    I jumper the inputs on my '68 50 watter
     
  4. windjamma

    windjamma Member

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    I think you can plug into ch2 and still use ch1 volume to add a bit of sparkle.
     
  5. Laplacian

    Laplacian Member

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    Y cord. EQ with the volumes.
     
  6. jmp

    jmp Supporting Member

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    I don't play a JMP Plexi anymore, but when I did I could never use the Normal input alone, even with the volume set midway and using pedals for OD/boost, as you do. It was just too dark a sound for me. If I plugged into the Normal channel at all it was only because I was jumping the channels to dial in a little low-end. I will say, though, that I owned several 50 watt heads over the years (originals and reissues in both stock and modified form). Some were much brighter overall than others. A few never needed any help from the Normal channel to sound rich and full.

    FWIW, Clapton always plugged into the Normal input on his 100 watt Plexis when he used them back in the 60's. If you look at Cream concert photos you can observe this. Obviously, it worked very well for him even when going through a treble-robbing wah-wah pedal and a pair of white coily cables.
     
  7. Third Stone

    Third Stone Member

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    Yes, it can work well with everything cranked, except the bass.
     
  8. scienceguy

    scienceguy Supporting Member

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    I'm pretty sure that's how Barry Bailey of Atlanta Rhythm Section ran his 50W plexi. Channel 2, wide open, no jumper, bass set low.
     
  9. JubileeMan 2555

    JubileeMan 2555 Member

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    The more I'm reading about this subject, it seems taking the Mixer Cap out of the circuit all together would be an even better solution. Right now, the normal channel bleeds treble off to the Bright channel and I'm curious if removing the mixer cap would bring the channel to perfection.
     
  10. Frank Speak

    Frank Speak Member

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    No, because I have a Germino Club 40 (1986 clone) which is a bass circuit. That said, I've started occasionally running a Y cable into both channels. That's a cool sound.
     
  11. Beam Tetrode

    Beam Tetrode Member

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    That would be the same circuit as the Marshall PA heads.
     
  12. Steve73

    Steve73 Member

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    Yeah, I use the Normal input all the time if I am playing my Superbass clean with pedals up front. I find the EQ is more balanced across the board in the Normal input while the Bright channel is well, too bright.
    When I am attenuating the amp and cooking it, I run a Y cord between the inputs as it seems to have more punch and I want more of the Bright channel as it gets a little mushy in the Normal channel alone.
     
  13. imguitardan

    imguitardan Member

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    I cut the brite cap on Vol I and it's much more useful. Then I put a 250pf cap on the bass channel (sounds like channel one) so I put a 120pf cap on the brite channel to get that JTM45 vibe. It's killer now.
     
  14. Dave_C

    Dave_C Supporting Member

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    Spent a lot of time experimenting with the inputs on my Germino Monterey 100 when I first got it and for quite some time afterwards. I always come back to greatly preferring the high treble channel with volume around 4.5 with pedals. The normal channel is amazing too, but just a bit too dark for me, unless it's being cranked for the Clapton/Cream thing.

    Bridged is cool but just not as clear and pure as high treble, IMO.

    I get no harshness whatsoever no matter WHAT I do with this amp! Not sure if all this applies to the lead voiced amps though.
     
  15. DICKIE C

    DICKIE C Member

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    I use both inputs on my Germino and my Marshall. The Marshall is jumpered sometimes, I don't hear a need to jumper the Germino. All depends on the guitar I'm using and what I'm going for at the time. I like it all.
     
  16. mudster

    mudster High Prairie Wrangler Silver Supporting Member

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    I like that channel and I liked plugging into that one and jumping to the other instead of vice versa. Just sounded better to me.
     
  17. Zingeroo

    Zingeroo Member

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    The normal channel doesn't bleed treble off to the bright channel. The bright channel bleeds treble off to the normal channel. Nonetheless, you can try lifting one side of the cap up.
     
  18. Frank Speak

    Frank Speak Member

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    Bridged definitely is not as clear. Actually, it does a find job of replicating sag; kind of squishy/loose vibe, IMO. I dig it with both volumes on about 3-4 (10:00). It's a beautiful "clean with just a touch of hair" sound, IMO.
     
  19. JubileeMan 2555

    JubileeMan 2555 Member

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    No, when you plug into the normal channel, that cap over the mixer resistor connected to the bright channel funnels off highs to the bright channel's vol pot ground.
     
  20. paulscape

    paulscape Member

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    I do a bit of blending. Its a tad thin just on bright and a tad gainless and dark on the normal. Blend gives a good mix. I also have the bright input push pulled (bright cap) and a fat 'switch' installed in the location of one of the other inputs.
     

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