How to recreate the famous Dookie modded Marshall amp?

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asclafani

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Trying to make a Green Day preset.
Billie uses 2 100w Plexis, so I'm using the PLEXI 100W 70 since that should be the same amp. His amps are both modded- the top one is the famous Dookie/Martin Golub mod, which "cascades the front end and adds a master volume". What does cascading mean, is it the same thing as jumpering inputs? There's no specifics of what the Dookie mod actually is or how to do it, so all I know is it basically changed the amp circuit to a JCM800 by adding gain and modding the tone stack. The bottom amp has an SE lead mod, which adds a tube for more gain.

So if I'm using a PLEXI 100W 70 as my amp in AFx, how can I replicate the mods? Do I just increase the input trim to add more gain than the amp would normally have? Do I turn the saturation switch on? In the actual amp circuit, how does a JCM800 differ from a 70s Super Lead reissue?
 
IIRC it’s not far off a jcm 800, just with some leftover plexi values in the gain stages. I’m sure most of the regular or modded Marshalls will get close. I think Ceriatone has a layout online, could maybe check that and see what circuit it’s closest too. (EDIT: http://www.ceriatone.com/ceriatone/wp-content/uploads/2021/03/Ceriatone-Dookie-ModSuper-L.jpg )

Before I had an FM-3 I recreated some Dookie tones with the Plexi in Helix. A 1960BV mic’d with a 57 and 421 blended together instantly got the tone for me, I think it’s a pretty generic Marshall sound plus getting the cab+mic side right.

You could try adding a gain stage to one of the plexi’s or try one of the 800/2204’s or Atomica/Friedman/etc.

 
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Coincidentally, I recently went back and listened to some old Green Day. Of course a Green Day rig rundown appears on my YouTube feed.



They get into the amps at about 8:20. It’s also known as the Bradshaw mod. When I searched that…. I found this:

https://www.kemper-amps.com/forum/index.php?thread/30861-jcm800-dookie-mod-cascading-gain-mod/


In summary, it seems like the starting point was actually a 59 Super Lead with cascaded gain stages and a master volume. Liam Thompson’s post there was quite informative.

So basically a JCM 800 already has the mods and is basically ready to go.

This part was key too:

“Naturally an old Marshall Super Lead modded for master volume and cascaded gain stages will sound a touch different to a JMP2203/JCM800 but not much, once modified in this way the circuit is I'd say 95% or more the same. You will generally find a good old Super Lead will be a touch warmer and looser in the bass, while a late 70's JMP MK2 or a JCM 800 will be a bit tighter, more aggressive and brighter.”

Sean Meredith-Jones
 
smj said:
59 Super Lead with cascaded gain stages and a master volume. Liam Thompson’s post there was quite informative
Click to expand...

This is what the Jose mod did which is the basis for basically all modded Marshalls (like Friedman etc) and the 2203/“jcm800” circuits are kind of like Marshalls take/advancement of that (using a cold clipper on one gain stage).

Cascading channels on the plexi means both channels are running simultaneously, cascading means one runs into the next. It’s quite common to tinker with resistor and capacitor values for these stages so things sound right, as well as adjusting bright caps.

It’s also common to play with phase inverter values (controlling how much bass gets through the power amp), and the nfb circuit (overall damping/looseness of the amp as well as presence and depth circuits).
 
MirrorProfiles said:
It’s also common to play with phase inverter values (controlling how much bass gets through the power amp), and the nfb circuit (overall damping/looseness of the amp as well as presence and depth circuits).
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One philosophy of high gain amps appears to be to get a lot of the distortion in the preamp (before the phase inverter), and then use a high headroom tube power amp to smooth out the harmonics a bit and supply the power to drive the speakers. This often sounds more powerful than if the power amp is clipping. A high gain preamp and a distorting power amp can often turn to total indistinct mush.

To my ears, what you hear in most cases in amps like the 5150 and Marshall 2203 is a furiously distorted preamp into a power amp cranked to the point where the power amp is starting to work hard but not adding much distortion itself. The power amp adds a lot of critical tone shaping and feel, but still conveys the power in the preamp tone with its headroom.

IME with modding amps, the real critical stage in a Marshall amp is the phase inverter. If you poke around in a NMV Marshall while it is clipping, it's surprising how little the power tubes distort as compared to the phase inverter. It's why a PPIMV sounds good in a NMV Marshall. But if that stage clips with a high gain preamp, it can really turn into a mess.

Strangely enough, the "clean power amp with distorted preamp" is how some Dumbles work, the distortion is mainly in the preamp and the power amp is designed to be relatively clean and have a lot of headroom available.
 
Exactly. What I meant with regards to the phase inverter is how much low end it lets through which really depends on how the preamp is voiced. With more high gain amps, more low end gets filtered out and added back in later in the circuit.

An SLO has more low end coming through the phase inverter than a 2203. Likewise a JTM45’s phase inverter let’s more lows through than a 2203. A Dirty Shirley is a 2203 preamp and JTM45 poweramp.
 
Dookie mod is a variation of CAE 3SE Crunch channel, with components value closer to a regular Plexi and the classic Marshall power amp with just a bit more negative feedback. Lead mod is straight CAE 3SE Lead channel into a Marshall power amp.
You have both CAE models available in the FM3 so you know what I mean...
 
To answer the OP question about jumpering: Cascading is running the two preamp channels in series, or in other words, running the guitar signal into one channel of the preamp tube and then running the boosted output of that into the front of the other channel of the preamp tube. Jumpering is running them in parallel, or running the guitar into both channels of the tube, and then combining the two channels together after the preamp tube.
 
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Re: doing this on Fractal.... I would start by using one of the "jumped" Plexi Models... and then for a slight bit of gain increase, engage the "Saturation" in the preamp section and set it to on or "ideal". It's a pretty clean way of adding more gain to the preamp section w/o altering tone. Still having the jumped amp going... that might be enough gain already w/o adding more. Though, in the virtual world... so many ways to up the gain... but this could be a place to start.

Sean Meredith-Jones
 
smj said:
Re: doing this on Fractal.... I would start by using one of the "jumped" Plexi Models... and then for a slight bit of gain increase, engage the "Saturation" in the preamp section and set it to on or "ideal". It's a pretty clean way of adding more gain to the preamp section w/o altering tone. Still having the jumped amp going... that might be enough gain already w/o adding more. Though, in the virtual world... so many ways to up the gain... but this could be a place to start.

Sean Meredith-Jones
Click to expand...
It’ll add more saturation but that parameter is to simulate diode clipping (such as in a Jose mod) which is a different flavour of gain and changes the compression characteristics.

Using natural mode for the boost is like adding a gain stage in front of the circuit - IIRC the extra gain stage on these mods is added in the middle of the preamp but it won’t make a huge difference. Any of the modded Marshalls/plexi‘s/CAA/Friedman/Atomica etc should all get pretty damn close
 
By the way, there are some isolated tracks on YouTube where you can listen the guitar tone out of the context of the entire band and it's not that great.
IIRC same amp was used by Rancid on And Out Come the Wolves, stellar album.
I think in both cases the entire band and the quality of mixing and mastering made all the difference.
Jerry Finn was involved on both, and whatever he touched was pure gold.

I've had Dookie mod in my 2203 for a short period, it was a one trick pony, very gainy, although quite cool and percussive with gain below 10 o'clock, surely a fun amp but nothing crazy. It also was much better in the room than on recording.

As for your request I had few minutes the other day, CAE Rhythm amp with tonestack changed to jcm800 into a 4x12 Greenback cab with 57+421 and a touch of room mic got me really close. Do not forget quite a bit of reverb.
 
I used this link and watch a Pete thorn video on Jose modded Marshall to create my “fractal Jose”

Post phase inv, variac, preamp boost for tone shaping…etc…I didn’t do the “2 amp idea”…didn’t need it…used the boost and also a “klon” od from the drive1 in front
 
I’d either:

1. choose one of the many models based on a hotrodded Marshall (many of which are based on a plexi but add a gain stage).

2. Use a plexi model and enable the preamp boost feature to approximate adding a gain stage, and utilize the master volume (which Fractal usefully adds to every amp model …) - this is what I use for most of my ‘hotrodded Marshall’ tones.

3. If it’s possible to defeat the cold clipper (?) on any of the 2203/4 or similar models that would - all other things being equal - be akin to cascading the inputs of a plexi and adding a pre-phase inverter master volume.
 
CAGOPOCO said:
Dookie mod is a variation of CAE 3SE Crunch channel, with components value closer to a regular Plexi and the classic Marshall power amp with just a bit more negative feedback. Lead mod is straight CAE 3SE Lead channel into a Marshall power amp.
You have both CAE models available in the FM3 so you know what I mean...
Click to expand...
Does the Dookie mod have 220k on the plates of the first 2 gain stages?
 
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