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Lee Jackson Marshall mod?

12/31/2004 3:28 PM
Glen Lee Jackson Marshall mod?
Has anybody heard a marshall moddeed by Lee Jackson? If so did it sound good,muddy, peircing highs, ect? thanks
1/1/2005 8:01 AM
An old roommate of mine had one of the old Metaltronix amps that LJ used to make. It did the 80's distortion thing pretty well, but not the phenomenal crunch of the old Marshalls. I wouldn't call it "fizzy", but it was mostly tuned for the Metallica sound from the first or second album, to my ears. Of course, it's been 15 years since I heard that amp, but I do know he sold it rather quickly and went to old Super Leads.  
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1/1/2005 9:09 AM

I have heard a few, actually borrowed a modded 50W Marshall head several years ago. IIRC it was a master volume model (2204). It basically had an added stage after the tone stack, as well as a PPI master volume. It sounded very buzzy and thin, but I didn't crank it up so high that the power tubes distorted. Lots of gain though. I didn't like anything about it.
1/1/2005 9:16 AM
Dai Hirokawa

there's sort of a tribute site, which has a schemo of the pre and power of a Lee Jackson amp--might be of interest:
1/1/2005 12:14 PM
Mr. Droopy-Drawers

It has to be a tribute site. You can tell whomever drew the schematics has European schooling, while Lee is a borderline redneck. The few missives I was lucky(?) enough to receive from Lee contained so many grammatical and spelling errors, that I wondered who really wrote them. Then I see the same types of errors in the 'tribute'. Hmmm.  
The Lee Jackson modded Marshall heads I had looked in were wired very sloppy, and they were noisy as all get-go. Lee even took a Dremel to the Orange Drops capacitors(!), so you couldn't read the values. Nice. I could steal the values where you stole them from, Lee; Orange.  
The modded heads are a sonic example of the tone sought after from that era; thin and buzzy. The people I knew sending Lee their Marshall were out $600 IIRC. Now they can't sell the head for half of that. I wouldn't do my Marshall that way. Look for a used head with the mod already installed. You'll save $600 at least.  
*WARNING* This is just one man's opinion. And it is worth exactly what you paid for it. The views and opinions expressed here are not necessarily those of any sane and rational person, living or dead, real or imagined. Thank you.
1/1/2005 3:38 PM

Hmm, while pondering this a few more details came to mind. All these are from memory, so please take them with however many grains of salt you wish.  
He also changed the presence control cap to 0.68uF. The PPI MV was a one-pot type with a switch, much like you see in a Matchless. The preamp was very similar to a Lee Jackson Metaltronix rack mount preamp, with that one stage after the tone stack, and the switchable treble cap in the tone stack.  
The topology is very similar to the OD channel in an early eighties Fender Concert. This amp as well as the others (Super Champ among others) are mainly known as being Paul Rivera designs, but I read somewhere that Lee Jackson claims to have input on the designs also. Because of this, I made a minor change to the Concert OD channel (330k grid resistor into the OD tube) that really smoothed out the OD sound.
1/1/2005 2:08 PM
i wanted to know because on ebay and lee jacksons site he is selling a dvd and vhs that shows you how to do his marshall mods. but from what i'm reading here it may not be worth it! anymore comments or opinions please let me know. Thanks!
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