Marshall Lead 100 Mosfet Amp
The Marshall Lead 100 Mosfet model 3210 amp was produced in the mid to late 80’s. It was one of Marshall earliest solid state amplifies and predates the Valvestate and MG series of solid state amplifiers.
A mosfet is a type of solid state transistor. Mosfet is an acronym for
Metal Oxide Semiconductor Field Effect Transistor
The lead 100 mosfet is loosely associated with the JCM 800 line of tube amps. The physical size of the head is a little smaller than a JCM 800. There are two channels that share a common EQ. The amp has an reverb and effects loop. There is an optional two button footswitch for boost or reverb. Without the footswitch plugged in you can actually combine the clean and gain channels for some different tones.
The voicing is similar to a JCM 800. It’s not a modern high gain amp and delivers more of a crunch tone. The amp is quite capable to pull off classic rock tones such as AC/DC and Aerosmith and early Def Leppard. To get more modern distortion tones or a real singing lead a boost is required. The clean is not totally clean and has some grit to it.
Like most older Marshall the tone controls are basically useless. The treble has the most effect on the tone. The mids and bass are much more subtle. Thanks in part to the limited tone controls it’s hard to dial in a bad tone. There seems to be a high pass filter which limits the bass response compared to some modern amps.
Another thing I really like about the amp is that it is a great head to run a POD or floor processor through. All you have to do is plug the modeler into the effect return and you bypass the preamp and go straight into the power amp. The bass response is totally happening when bypassing the preamp in this manner.
In the picture below my head is sitting on top of a MG412A cabinet. I know a lot of people knock the MG cabs but this setup sounds pretty good to my ears.
Overall this amp is a steal for the price. They sell all day on ebay for about $200-$225. It can get classic Marshall tones on a budget and it looks cools as hell. Thanks to the effect return you can also plug a modeler into this head which really adds to the versatility.
thanks for this info. i have heard that these amps sound better at high vol. and the mosfet does not kick in until your alt half vol. is this correct.
In general I don’t think this amp sounds any better at high volumes due to the mosfet design. Maybe by pushing more air at higher volumes you get a little more thump from the cab but I think it’s more of a speaker issue than a mosfet issue. Your mileage may vary.
Hi,
I’ve bought one of these and have it plugged through a valvestate 2×12″ 150w cabinet which alo sounds good.
Question: Has it a valve in the preamp like the later valvestate amps ?
What marshall pedal do I need to get to work with it to change the channels?
Thanks.
Thanks
I have been using one of these heads for the better part of 20 years. I always felt that it lacked a bit in the low end but this has easily been remedyed by running a Boss EQ pedal through the effects loop. You would be amazed at the versitility in tone after making this modification.
If it sounds thin, or the tone controls are too subtle, replace the electrolytes. There is plenty thump to be recovered. Also, if you haven’t changed the MOSFETs at the ouput in the last ten years, give it a shot. The amp will clean up somewhat, and ad some attack and sparkle as well as volume.
Mark: There are no valves in this. It is not a hybrid design. You’ll need a double footswitch (stero plug).
Hey webmaster,
I’ve had my mosfet for about 5 years and the person i bought it from recommended plugging a cable( not connected to anything else) into the floorswitch input to get that gain boost going.
when i would do that the boost light would come on and the amp sounded awesome, so i continued doing that until recently
when after i played a show not too long ago, the sound just went dead.
even though the red boost light stayed on with or without the cable plugged into the footswitch input and the volume was still cranked, the gain was totally gone. it’s really light and fuzzy and just sounds like it’s totally burned out.
now my amp seemed to have bitten the dust.
any way i can fix this? or any idea of what might’ve happened
Hi,
Did the amp smell like something fried? My amp acts up once in a while due to the effects loops jacks on the back. There’s a few things to try. Try to hook up something in the effects loops to see if that fixes the problem. You can even just jumper between the input/output to see if that helps.
Also you can plug directly into the return jack of the effects loops with a pedal or guitar to see if the problem is in the power amp or preamp. Be warned there is no way to control the volume from the amp when plugging into the return jack so you will have to use the level control on the pedal or the volume knob on the guitar.
Hope this helps
I just got this head and a Marshall 412 cab for 4and a half.It was in my buddy’s shop forever and starting a band I wanted the Marshall power.I played in a band once were the guitar player had a hundred different heads.I just want the Marshall sound and the growl,whats a good setting for the EQ knobs.I’m using a DigiTech multi affect box to distort it cause I’m in my garage practicing but when I play live and get to turn it up why distort it, it defeats the purpose of having a Marshall is the way I see it.Like cooking a fine steak then putting ketchup on it.
If you want to just boost the Overdrive on the Marshall (keeping that Marshall tone and not distorting it) my suggestion is to set your EQ how you prefer and use an Ibanez Tube Screamer with a Boss EQ (to give it that extra umph). Experiment. These are bad-assed amps if utilized correctly.
Hey webmaster,
Just bought one in excellent condition from guitar center. I was just wondering if this amp is good for early Van Halen? Is its sound anywhere comparable to a 59′ Plexi? Please Reply, thanks.
You can get close to VHII tones, not so sure abput VHI stuff though. It doesn’t really sound like a hot rodded Marshall or Splawn.
I suppose you could experiment with boosts and EQ’s to get close.
Hey man, I just got it finally today. I found out that if you really push a phase 90 on it and raising the highs and bass and lowering the mids on the amp, that you can get that kinda of van halen 1 hot rodded plexi tone with no boost. Hope that helps.If you try this out please reply, thanks.
Hey webmaster, just got my my mosfet today and I was wondering does the gain on the amp only work if you have something plugged into the footswitch jack. I can stick any cable in the jack and the push-pull gain will work, but when I take it out it goes back to the clean channel. Is it suppose to be like this, please reply!
Hey webmaster,
I just bought a mosfet and I’m digging it. The only problem is a real loud hum when I turn my big muff on. Any suggestions on what’s causing it. The pedal is brand new and the hum won’t go away when the strings are muted. Thanks…Rad site by the way
I just bought a 3210 and i’m tryin to figure out the speaker connection.
It says 4 to 16 ohms and has two connectors.
I got a four ten cab at 8 ohms where do i connect it?
four is left 16 to the right or does it matter at all?
Pat
Hey, gotta say that I’ve had one of these Marshall Lead 100 Mosfet amps since around 1988 (bought second hand) – used it heaps.
Initially in a 80’s thrash metal band (the other guitarist used a Marshal valve amp- we got great differentiation). I hooked up an Ibanez Tube Screamer and a Boss HM-2 into the clean channel…… old school heavy sound.
Hell, I even used it initially for a Black Sabbath tribute act… and still pulled a sound (to the surprise of the tone purists),
Just recently I’ve used it slaved to a MI Audio amp for a brutal combination of heavy oomph (MI Audio) and snarling, sizzling hack-your-head off bite (Mosfet).
Plugged the MI Audio into a 4×12′ quad. Plugged the Mosfet into a Laney 2×12 box.Never would have guessed that would work!
Some dodgy pot replacements, input jack changed over the years but thats about all it’s needed. Sturdy as.
Very versatile little amp.
I bought this amp in 1989. Was my first real guitar amp. The pros were that it was a 100 watt head in a small size and that it was reliable, the cons were it sounds like you are playing on AM radio. All my guitar playing friends at the time had Crates which were also all solid state and they were WAY better sounding. I had the whole mid stack setup that came w/ the head, w/ top and bottom 1×12 cabs. One word of advice, the head sounds better w/ a full size cab, the 1×12 cabs just added to the AM radio sound.
Josh,
Sounds like you didn’t know how to setup the Marshall, or you need to clean the wax from your ears. SS Crate amps back then sucked then, as they do now compared to the Marshall Mosfet or even the original Valvestate line. I have two Mosfet heads, one running through a Peavey MS 4×12 loaded with WGS Reaper 55HZ and the other running through an old Roland 4×8 cab that is modded to look like a Marshall cab. Either setup sounds awesome and has every bit of the classic Marshall drive and sound. I’ve owned a ‘76 JMP 50 non master head, two JCM 800 2204 heads and a DSL 100. The Mosfet holds up very well when compared to these tube models. The biggest thing is tubes vs. solid state design. If your a great player, then the Mosfet can sound just as good and most people at a gig won’t know the damn difference unless they are gear obsessed snobs from the Internet.
Hello,
i bought this one in 2001 in a guitar center. It was my first guitar amp when started to play. Nowadays it stays in the corner of my room. (out of use)
But last week i played since many years again with it and i have to say the sound is still good like for example in the early days of ac/dc….:O) I like it!
I use to have the brown one togehter with 4×10 brown colored box.
What’s the best way to ship one of these?
i can score a lead 100 mosfet head for next to nothing. i play heavy sludge metal tuning to b or a and run through a sunn model t, orange/carvin 4×12 cabinets with a fulltone pedal. do you think that i can abuse the marshall like i can the sunn? also i picked up a h&h vs 100watt musician head 1976 if any one has any info about it would be helpfull. thanks TUNE DOWN AND TURN UP!!!