Top 10 Marshall Artist Signature Amp Heads Explained

By Justin Beckner and longtime Marshall employee Danny Thomas.

For this article, I enlisted the help of my friend Danny Thomas, who was the engineer who project managed and built the Marshall Artist Signature Amplifiers. Daniel worked at Marshall from 1985 until he retired in May of 2015. During those 30 years, he held a multitude of distinguished titles such as Signature Series Development Manager, to Custom Shop Coordinator, Production Engineer, Test Engineer, Service Engineer, Development Engineer, and Factory Painter. I want to thank Daniel for his help in explaining Marshall's signature heads.

Slash – 2555SL

This was the first signature amp model Marshall came out with in 1996. It was a limited run of 3000 amps based on Slash's 1987 2555 Silver Jubilee that he used during the Appetite for Destruction tours. These were pretty much a straight up reissue of the 2555 Silver Jubilee amps, using Dagnall transformers. Although the transformers in the 2555SL might have been wound in Malta instead of Bedford.

The Slash Signature amp came about in 1996, you may recall this was around the same time he left Guns & Roses. Around that same time, he lost some equipment and asked Marshall if they could help him replace his whole backline. That request morphed into the signature amp we have today.

Zakk Wylde – 2203ZW

Zakk had played JCM 800 heads for years. Zakk's signature head features 6550 tubes instead of the EL34s that sold in the UK, originally. But that is the only "modification" on that amplifier aside from the bullseye on the faceplate. They made 600 of them and they sold out within a few hours. Both the Zakk Wylde and Slash 2555SL Signature heads were more of a cosmetic variation than anything else.

Jimi Hendrix – Super 100JH

In 2006, Marshall released the Jimi Hendrix signature amplifier, based on years of research by the engineering crew, led by Danny Thomas, they tracked down many of the amps Jimi used through the years, talking to friends and bandmates – searching for any information about what he liked and didn't like, and built this Super 100 based on their findings. They spoke with Eddie Kramer, who was especially helpful, and even Lemmy, whose recollection was dropping acid and driving Bletchley in a Bedford van to collect some gear from the factory. The original idea was to produce a close replica of a 1967 Super 100 as that was the first amp Hendrix had purchased. It features KT66 tubes and Drake transformers, like the original, but minor tweaks to the circuitry to allow for a bit more treble. The tone stack is similar to the latter Super Leads. When bands started player larger venues and audiences were louder, artists wanted more treble to cut through the crowd noise. So the circuit improvements in the Super 100JH were pretty much just stock circuit improvements that would have been done at the time. Steve Dawson, the project design engineer, put a lot of time into getting the sound details spot on. Only 600 were made, along with period-correct matching cabinets (1982AJH and a982BJH) which are 7 inches taller than a standard 1982 cabinet. The speaker cabinets made big difference in the sound as well.

Kerry King – 2203KK

The 2203KK was designed by Santiago Alvarez and project managed by Danny Thomas, along with Kerry's tech at the time, Armand Crump, who tragically passed away in 2012. The Kerry King Signature 2203KK is an amp based on Kerry's favorite JCM800 which he dubbed "The Beast". Kerry sent the amp to Marshall, thinking it had been modded somehow, but it turned out to be a completely stock 2203 head, which was originally built in 1996. It's true that some stock heads do leave the factory sounding slightly different than others. Often this can be triangulated to variances in the manufacturing of certain components like resistors or capacitors. The 2203KK is basically a stock 2203 with Kerry's own 10 band EQ parameters (based on his BOSS RGE-10, which he had been using prior) built into one knob and an extra gate built in. It uses KT88 tubes in the power stage and ECC83s in the preamp stage.

According to Danny Thomas, "'The Beast' was a stock 1996 built 2203, no mods, it was just that all the component tolerances "worked". On scope it behaved exactly like a stock 2203, but when amplifying a full range of guitar signals it just loved to "thump" in the low end and present a real guttural bark, tight, and roaring like Cerberus' three heads shouting.

[As for the EQ] Santiago did the circuit work and immediately knew what to do, the EQ was a "frown" and it produced a curve at 1k that looks like you're flipping the bird - Kerry loved that! And he used a noise gate that was far superior at tracking the input voltage, so you don't get that clunky shut off and it allows it to open more effectively. I can't recall exactly what the chip was, but it was such a simple and effective circuit. Krank had been trying to woo Kerry and had produced a monstrosity that simply had a 10 EQ gaff taped to the chassis. We produced a prototype late 2007 and I took it to LA for Kerry to try. He loved it immediately. It went straight into his rack and he recorded the next Slayer album with it. We then provided him with two rigs, six heads for each, and did a little fiddling to synchronize the noise gates. It was a brilliant project and Kerry and Armand were brilliant to work with. And their business associates understood what Kerry wanted and what Marshalls could offer, so the deal was a breeze to negotiate and manage."

Randy Rhoads – 1959RR

In 2008, Randy Rhoads got a signature head based on his modded Marshall he used for the recording of 'Blizzard of Ozz' and 'Diary of a Madman'. Randy's original Marshall mod was done by Phil Millichamp – in fact it was Phil who suggested the mod to Randy. Those specs were later copied over to the 1959RR Signature Head by Danny Thomas. The most significant mod was a cascade mod – a hookup wire looped the signal back through the first valve. The result was essentially a boost in the preamp stage, giving some nice overdrive and distortion that could be controlled by a faux master volume. Cascade mods became somewhat common in the 80s, the US had a few builders like Jose Arredondo who were pretty well-known for doing them.

The following is from an interview that Danny did with MusicRadar:

"They took all of the equipment they received back from the Ozzy tour after Randy's death out of storage and brought it over, and we opened up the flight cases and took out the gear. We checked it through, drew sketches of the circuits, catalogued it, measured it, and took photos. Then we put that data into a prototype back here [at Marshall HQ in Milton Keynes]."

As for the cascade mod, Daniel recalled,  "Surprisingly, when I was checking the circuits, I did find something that was out of place, a resistor that had been cut and moved, so I duly noted that. I also noted who had wired and tested it, and when we got back to the factory I called the test manager from the day. He remembered meeting Randy Rhoads and told me he'd tested and modded the amp for him. I asked him what he'd done and he'd cascaded the first valve: the inputs from the normal channel get fed back through the input of the high treble channel. He said we used to do that occasionally for some people when they wanted a bit more gain and guts, and, as Randy had asked him if there was anything he could do to get it a bit beefier, that's what he did."

When speaking about how he incorporated the mod into the 1959RR, Daniel explained, "Channel one is a normal '59 'Plexi' and channel two has the mod on it, but the thing is to pull back on volume one. Randy actually had both volumes set to about six and six and a half. So volume two was driving a great deal in to the next half of the valve, and then that again was opened up a fair whack. You get it loud and you're getting in the zone. The other thing is to pull the bass down. Actually, the rest of his settings were presence to six, middle to five-and-a-half, treble to six-and-a-half: that should give an approximation of the tone."

Lemmy Kilmister – 1992LEM

The 1992LEM replicated Lemmy's iconic Murder One amp. I wrote an article on this amp at one point, so I'll go ahead and plagiarize myself here [I'll sue myself later…]

In the making of this signature amp, Marshall's engineers had unprecedented access to the original Murder One it is based on. According to Phil Wells at Marshall Amplification, Lemmy's Murder One is a completely stock 100-watt Marshall 1992 Super Bass model from 1976. Phil Wells has worked at Marshall for a very long time, Jim Marshall referred to him as his "top repairman" in the book The Father of Loud – he was with the company during the design and creation of the original Super Bass model and the 1992LEM model. He currently looks after the museum and archive at Marshall Amplification. So, there you have it, directly from Marshall, Lemmy's Murder One head is stock. His signature head, however, is slightly modded from the original specs of Murder One.

The 1992LEM Lemmy Signature amp head that went into production in 2008 [although Lemmy received and used his as early as 2007] is essentially a 100-watt Marshall 1992 Super Bass powered by four EL34 valves, based on Lemmy's 1976 model. However, the 1992LEM has an extra resistor added to the valve bass to prevent pre-amp feedback, a hum balance control was added, and there were one or two minor parts that weren't available when creating the 1992LEM, as by then they were forbidden due to health and safety. These were replaced with the closest modern equivalents. Also according to the folks at Marshall,

"Murder One did come in to the factory here every now and again for servicing and there are reports that Lemmy used to take the earth off Murder One so when it was brought in for service we had to repeatedly re-earth it!"

Danny Thomas worked on Murder One on several occasions – I asked him if he could confirm the amp's ground [Earth] being disconnected - as he recalls, "Murder One was always in the repair shop, by the end of every tour it had usually blown a transformer. Never had to replace the earth when I serviced it. Lemmy didn't go inside the heads, he just used to get bored on tour and decorate the outsides. However, Motorhead played a lot of shows and some were rather shoddy affairs, so perhaps some stage crews removed the earth when they had poor stage grounding problems.

I remember one time all the Motorhead backline came in completely blown to pieces, all the speaker cones had been shredded and everything was covered in black powder. They had had a pyro accident and set them all off at once and blown up the whole backline"

One famous owner of the 1992LEM is Tom Araya of Slayer - he used it to record the band's latest, and likely final record, "Repentless".

Paul Weller – Lead and Bass 1987X-PW

The amp that Weller is best associated with is a rather rare Lead and Bass 2100. They were only available via mail order for a short period in the 70s, these 50 watt combos are now very much sought after. So to celebrate Paul's 50th birthday, they made a reissue of that amp – a limited run of 50 featuring the MarhallArt® Digitally printed bullseye. A taxi driver in London bought 7 of them. They did another limited run of 50 in the Japanese market that did not feature the printing. Tech-wise, it is a 1987 chassis shoehorned into a 1962 cab – again, it was Danny Thomas who copied the circuitry components on Weller's original amplifier. The speakers were two G12C Greenbacks. The 1987X-PW came along with a certificate of authenticity, and all profits from this amp were donated to the charity Childline, as this is a cause that Paul and Jim were passionate about.

Joe Satriani – JVM410HJS

Joe Satriani had become familiar with the Marshall JVM as he had already been recording and touring with it, and by 2009, he had also come up with some ideas to improve the amp, and in his words "make an already great amp even bigger, bolder, more punchy and more dynamic." With this in mind Joe Satriani and Santiago Alvarez, the designer of the JVM, set to work on Satriani's own signature amp; the JVM410JHS.

Having designed the original amp, Santiago knew what the DSP was capable of – the DSP originally ran the reverb, but he re-programmed it to work as the noise gates. After three years of prototyping and testing out on the road, the JVM410HJS was released in 2012. It featured a noise gate for each channel, a tone stack tweaked to Satch's preferences.

Yngwie Malmsteen – YJM100

On first inspection this amp looks exactly like a 100 watt 1959 Plexi, but look a little closer and you can spot that the JTM or JMP on the front has been replaced with JYM. Inside the amp, we find a booster, noise gate, digital reverb and an FX loop all that can be controlled with a footswitch. On top of this there's the option to reduce the power to 50w plus valve fault indicators and self-biasing. To complete the lot the YJM100 comes complete with a red dust cover inspired by Yngwie's other love, Ferraris. Santiago Alvarez used this project as a research vehicle for the power attenuation and further improvements to the noise gate.

Slash AFD100

Slash wasn't just the first artist to have a signature Marshall Amplifier, he was also the first artist to have two. This amp was meant to replicate the tones used on the Appetite for Destruction record [you can check out my article on the gear used on that record here. The finished amp has two modes, #34 and AFD. #34 is based on Slash's favorite JCM800 2203 where as AFD mode brings in additional gain that's modelled on the fabled missing rental amp. Slash doesn't actually know where S.I.R. #34 is, which is why Santiago Alvarez and Slash worked together to nail the tone by listening to Slash's tracks from the original master tapes and created the tone circuit based on their listening sessions.

The AFD100 is unique in that it has a silver front panel just like a Silver Jubilee. It also features 6550 power valves, an FX Loop, Auto-Bias and a special feature called Electronic Power Attenuation, which is a further refinement of the technology used in the Yngwie Signature head. This functions basically like a Variac, it allows the player to reduce the amps volume output from the maximum of 100w right down to 0.1w without impacting its tone.

Only 2300 of these amps were made, but even rarer are the 100 AFD100SCE versions of the amp. These had the same sound and features, but also had a bunch of fancy cosmetic marketing features such as: mirrored front and read panels, black snakeskin covering, silver piping, mirrored rear vents, a rear plaque signed by Slash himself, flight case, dust cover, production certificates signed by the Marshall staff involved, and even a personalized, and numbered AFD100 workshirt. Marketing is always a big part of any signature amplifier build, usually this presents more hurdles and barriers to the build than anything else.


Things That Never Came to Be

Finally, I asked Daniel about some signature Marshall heads that almost happened or should have happened.  "I had been talking with Gary Moore for a few years and pursuing some ideas, but once again [other] people were trying to drive the project and in the end Gary and I sat back on it as it was quite insulting for him to be honest.

I was opening up a dialogue with the Young brothers [Angus & Malcom] and had done technical assessments of Malcolm's aluminum chassis 100 watt JTM head and Angus's JTM 50 and JTM 45s. Had made a start on the JTM50 - it was two el34s with a gz34. Ran about 43 watts, sounded killer. Malcolm's 100 watt was a nest of Mike Hill line outs and other paraphernalia but at its heart a very basic early 100 watter and it sounded like God Shouting!

There was another Zakk head in the pipeline, but [it didn't work out]. Zakk was at the start of his Wylde Products idea and wanted to brand the amp with his name.

I had an open door with Jeff Beck and was looking at possibilities. And Jimmy Page was keen to start a conversation. But to be honest, how many 100-watt amps can you make and sell in a very limited market?"

Bonus Cabinet Mention: Dave Mustaine – 1960DM

Megadeth's Dave Mustaine was the first artist to ever have a signature series cabinet. There are actually two cabinets, for the traditional full-stack - the angled 1960ADM and straight 1960BDM, each cabinet capable of handling 280 watts. The cabs are loaded with four 70w Celestion Vintage 30 custom speakers and were air sealed to enhance the projection and punch. Cosmetically, they have a diamond-punched metal grate instead of a material fret cloth. The finishing touch is a custom plaque in the bottom corner of each cab that has both Jim Marshall's and Dave Mustaine's signatures. The cabs even came complete with an exclusive DVD presented by Mustaine himself, an owner's certificate, and a heavy-duty dustcover with unique artwork.

Danny stated that they produced a one-off 1936 2x12 version when Mustaine did a concert with the LA Symphony Orchestra.

Marshall also made a 15watt micro stack featuring custom-voiced channels that Mustaine himself dialed in. There were also a further set of voices unlocked by plugging in the foot controller. This could be considered a signature amplifier as well although Dave doesn't play it live.