Mods to make a Marshall Class 5 more warm, full, hifi?

Discussion in 'Amps and Cabs' started by dnauhei, May 7, 2015.

  1. dnauhei

    dnauhei Member

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    I've got a Ramrod in there. I also have a 12AT7 (or something like that) in V1 to lower the gain. I can get a nice marshall on the edge of breakup tone out of it, which I like. But I would like it to be fuller, warmer, more hifi.

    I know there are a lot of mods out there, but I am going for something specific. Any ideas on this?

    Or, given the wattage and 10" speaker limitation--am I barking up the wrong tree?
     
  2. oldschoolguy

    oldschoolguy Member

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    I play mine thru a 2x12 cab with a blue and a Scumback. Sounds much, much better. Turn the bass down and the volume up. No mods to the amp itself. YMMV.
     
  3. dnauhei

    dnauhei Member

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    Hah! No room in the "amp room" for a 2x12 cabinet. I was thinking more in terms of a tweak to the circuit, an bigger OT, a different speaker . . . . Ideas?
     
  4. garret

    garret Member

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    This, friend has one and didn't care for the sound at all through the stock speaker.

    Pugged it into my 2 x 12...sounded great!
     
  5. 8len8

    8len8 Member

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  6. Gnarlly

    Gnarlly Member

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    What settings are you using? I have the head and matching cab setup, and owned a couple combos in the past (sold because the combos rattled the tubes too much). I currently run a NOS 12AU7 in V1 to lower the gain, bright Chinese 12AX7 in V2, and a bright Russian EL84 for power. With those tubes, I run the volume, treble, and mids all on 10, with bass on 1. This lets me go from nice cleans to 80's hard rock tones with my guitar's volume. OCD or EQ for boost (used mostly as a treble boost).

    But even with bright tubes and treble and middle maxed, the Class 5 is still a "warm" sounding amp by Marshall standards (think more like JTM45 warmth, but with some JCM800 snarl and aggression). Personally, I think the stock 10" speaker is a perfect match for the amp. I've tried the amp with a bunch of other speakers, and while I thought it sounded good with 12" Greenbacks and WGS Vet30 and ET65 speakers, it seems to sound best to my ears through the stock 10" speaker once it has broken in very well. I run the amp miced for band practice, using in-ear monitors, and it sounds big and full in the mix.
     
  7. Lothar34

    Lothar34 Supporting Member

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    http://www.mylespaul.com/forums/squawk-box/123816-some-mods-marshall-class-5-a.html

    Lyle's mods are legit, cheap and easy. Just a few caps and resistor swaps. Even if you just do the input impedance & tone stack mod (which is what I ended up with when I had mine) it makes a huge difference. No more woofiness, more headroom, less boxiness, etc. Don't bother w/ the choke mod- I had a lot of problems w/ it (and so did many others). Eventually, even Lyle himself suggested that maybe the choke mod was more trouble than the potential benefit.
     
  8. DaveKS

    DaveKS Member

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    Fuller, warmer vs hifi are to me asking for two opposite things. Full/warm to me is asking for richer, more defined and more bass/lower mids. More hifi is asking for more clarity and definition top to bottom including the extreme top end which means harsher, more biting on top.

    If you mean more definition, clarity and presence in the warm end of guitar range look at a Tone Tubby 40/40. On bottom end it's the polar opposite of ramrod's undefined bass and lower mids.

    And to me for warmth, 12at7 is exactly the wrong tube in a v1 preamp slot. Harsh, biting odd order harmonics and overtones is all it will get you even though it is lower gain. They sound brittle and uninspiring.

    Try a old Sylvania 5751 or 12ay7/6072 if you want smooth, round, growling OD. GE brands of same models for just a touch more grit. Mullard 7247/12dw7 if you want same gain as 12at7. Any of these are vastly superior to 12at7 in socket built for a 12ax7. Now in a PI slot a 12at7 can work great, but off top my head I can't remember if yours has one.
     

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