Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups Warmoth.com
Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups Warmoth.com
Asher Guitars WD Music Products Amplified Parts Mod Kits DIY Nordstarnd Pickups Warmoth.com

Thoughts on this '78/79 2104 Master Lead 50w?

Discussion in 'Glowing Bottle Tube Amp Forum' started by Guitarteach, Sep 25, 2017.

  1. Guitarteach

    Guitarteach Poster Extraordinaire

    Aug 6, 2014
    UK
    Just picked this up at the weekend. A very lucky local find.

    Used it at rehearsals last night after some basic testing. It sounds absolutely spectacular. Blazing bright and clear with a Les Paul and my old 345.

    I'm having a good look inside now to see what jobs I need to do. Big Filter caps look original.

    I know it went back to Marshall some years back for a speaker change but there does seem to be a couple of other changes done. Hoping the experts on this circuit might shed some light on them.

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    uriah1, Il Duce and brookdalebill like this.

  2. brookdalebill

    brookdalebill Telefied Ad Free Member

    Age:
    60
    Nov 15, 2009
    Austin, Tx
    Great amp, what's not to like?
     

  3. VintageSG

    VintageSG Tele-Afflicted Ad Free Member

    Mar 31, 2016
    Huddersfield, UK
    Ooh, Samwha caps. Did they really cut the old ones out and solder the new to the protruding legs?.
    Replace them. Samwha had a reputation, deservedly so, for caps that went splut. Those may be after they fixed the issue ( electrolyte formulation? ), or they may be from before. Whatever. Many a South Korean panel TV had a dead supply shortly after the warranty ended due to Samwha caps.
    The only computer PSU I've had go postal on me was due to Samwha caps. This may have been due to the motherboard caps trying to escape ( guess who? ) or the PSU may have caused them to bleb and leak.
    Nichicon, Mallory, Panasonic, Rubycon ( get genuine! ). Whatever, a cap job is called for.



    Note. A search for Samwha capacitor quality does not yield promising results.
     

  4. Guitarteach

    Guitarteach Poster Extraordinaire

    Aug 6, 2014
    UK
    Thanks. Not heard of the brand before.

    I've got some new F&T big can caps on the way and I'll do the bias caps properly too when I'm in there with Nichicon or similar.

    Preamp and MV controls will get new pots and I'm putting a push/pull in for the bright cap.
     

  5. corliss1

    corliss1 Tele-Afflicted Gold Supporter

    Sep 13, 2008
    Lansing, MI
    Super common to see caps on Marshalls with the legs cut and new ones soldered to the old legs. Saves you undoing the input jacks and pots, flipping the board over, replacing stuff, and putting it all back together. Not saying that's the right way to do it, but common to see that type of work. However, if you plan to replace all the big caps, which you should, you'll need pull the board anyway to get at the cap that lives, and is wired, under the board.
     
    robrob likes this.

  6. Dacious

    Dacious Friend of Leo's

    Mar 16, 2003
    Godzone
    Awesome amp - last series before Marshall was bought by Yamaha and started cheaping out components. Pots separate. They can be variable but usually sound great. Master dimed (if you can) gain varied on input and control from guitar. I had the 83 single input combo and it was OK but hard to get consistent tone and had the 'bleed' issue.

    Solid PCB nice fat traces
     

  7. Guitarteach

    Guitarteach Poster Extraordinaire

    Aug 6, 2014
    UK
    I've already done some work on it. New input gain pot also switches the bright cap. Very versatile for SCs and HBs now at any volume or gain. Cleans are killer too with a Strat.

    Some big F&T filter caps are on the way and the PCB will be out for fitting one of those.

    This is everything you want and expect from an old Marshall. My poor old Mesa Boogie is jealous...
     

  8. robrob

    robrob Poster Extraordinaire Ad Free Member

    Dec 29, 2012
    United States

  9. Guitarteach

    Guitarteach Poster Extraordinaire

    Aug 6, 2014
    UK

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