New from Synergy: Marshall JCM800 Module

Marshall JCM800 Modified 100-watt Amplifier Head

100W, 1-channel Tube Guitar Amp Head with Tight Switch, Midrange Boost, and Gain Boost
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Item ID: JCM800MS
Marshall JCM800 Modified 100-watt Amplifier Head
Price:$3,449 and 99 cents
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Marshall JCM800 Modified 100-watt Amplifier Head
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Marshall JCM800 Modified 100-watt Amplifier Head
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Price:$3,449 and 99 cents
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A Modern Modification of an All-time Marshall Classic

True to the JCM800’s hard-rocking roots but not afraid to innovate, the Marshall JCM800 Modified celebrates a timeless Marshall classic with a host of modern, performance-minded appointments. From fueling the heavy metal of the 1980s when it first launched to its role as an alternative and punk icon in the 1990s all the way up to its status as a modern mainstay, the JCM800 boasts one of the most revered and recorded tones in guitar history. As such, the JCM800 Modified retains the rock-solid foundation of the original, mirroring its 100-watt power rating, straightforward EQ section, and gain-laden one-two punch of Master Volume and Pre-Amp Volume knobs. However, the eagle-eyed in the audience will no doubt notice the additional switches set directly under the control section — these powerful tonal tools unlock a cutting midrange boost, a fiery gain boost, and a tight switch to firm up your bass when dishing out ripping riffs and rhythms. Revised and ready to rock with even the most modded-out Marshalls, the JCM800 Modified elevates an all-time rock and metal classic without compromising on the style and sound of the original.

Turn up the heat

The JCM800 Modified’s first departure from vintage specs comes in the form of a high-octane gain boost switch. Flip this switch, and the JCM800 Modified’s already-formidable roar is boosted with a powerful injection of saturation, allowing you to effortlessly swap from old-school rock and blues tones to ultra-aggressive modern metal mayhem.

Clarity-enhancing midrange boost

Ask any of Sweetwater’s rocking lead players how they cut through the mix, and they’ll tell you that the secret lies in the midrange. It’s what gives your tone its cut and bite, and the JCM800 Modified’s powerful midrange boost switch might just save you the trouble of rigging up a green-colored stompbox. Lay down the rhythm with JCM800's time-tested, authoritative crunch, then engage this switch to instantly transform your signal into a screaming, solo-ready sound with enhanced depth, warmth, and articulation.

Tighten up your tone

When the JCM800 was first released in the early 1980s, low-tuned guitars had already been a staple in rock and metal for more than a decade. Still, with the rise of extended-range instruments, subterranean tunings, and extra strings within the realm of modern rock and metal, it can often be a challenge to keep your low end in check on older amp designs. Well, unless you’re rocking the JCM800 Modified, anyway — this amp’s tight switch surgically cuts out excess bass, keeping your chugging rhythms and riffs crystal clear in even the highest-gain scenarios.

Marshall JCM800 Modified Features:

  • Starts with an authentically accurate JCM800 foundation, then elevates it with myriad modern appointments
  • 100W of valve-driven fury, fueled by 4 EL34s and 3 ECC83s
  • Versatile gain-shaping controls include a Master Volume and a Pre-Amp Volume knob to dial in sweet saturation at any volume level
  • Straightforward EQ section includes a 3-band EQ and Presence knob
  • Dedicated High- and Low-sensitivity inputs
  • Midrange boost switch injects your signal with cutting clarity to slice right through the mix
  • Tight switch scoops out excess bass for a firmer, more defined voice
  • Gain boost switch dramatically turns up the heat, allowing you to take on all manner of gain-laden modern metal mayhem
  • Traditional Marshall aesthetics capture the vibe of a vintage JCM800 in all its glory

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Tech Specs

  • Type: Tube
  • Number of Channels: 1
  • Output Power: 100W
  • Preamp Tubes: 3 x ECC83
  • Power Tubes: 4 x EL34
  • EQ: 3-band EQ, Presence, tright switch, mid-shift switch
  • Inputs: 2 x 1/4" (high, low)
  • Outputs: 2 x 1/4" (4/8/16 ohms)
  • Effects Loop: Yes, Bypassable
  • Bias Type: Adjustable Fixed
  • Construction Material: Black Tolex
  • Power Source: Standard IEC AC cable
  • Height: 12.2"
  • Width: 29.52"
  • Depth: 8.27"
  • Weight: 45.19 lbs.
  • Manufacturer Part Number: 2203MS-U

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Reviews

really good
I dig it! Love to get to have a JCM 800 "stock boy" if mods are off, then toggle the mods in and it extends the range.

A stock 800 is not that "gainy" but with the mods here, I don't have to put a pedal in front if I don't want. That said, the included mods are not ultra gainy either so you still may want a suitable pedal in front.

I run this into a Marshall 1960A 4x12. Nice pairing!

For my best results, I'm using an Ironman II attenuator to give additional level control (letting me run the 800 at whatever levels I want), and a ISP Hum Extractor + Decimator II in the FX loop of the 800. With gain turned up, there's a significant noise floor, which the ISP does a great job of taming.

All considered, I like this 100W Modded version better than the studio version because it has more sonic range, better transient handling, and more sonic command, and I like this alongside than other amp maker's "british hot rod" versions because this is a (classic) stock 800 with extended range, and the Marshall has more command and sensitive feel vs. the others.
JCM800 Mod
Waited a bit for this one and it was well worth it. Excellent tones and great modification choices make this a malleable tone monster! Tons of gain and breakup at low volumes if thats your thing. Great tone changes out of the EQ so you can really dial in your Ts Ms and Bs. The JCM is the industry standard and this eclipses it...even the late 80s and early 90s ones. Sweetwater guided me through the order process and notified me when it shipped. Alex Mattingly, my regional advisor from Sweetwater is the best!!!
Music background: Rock
Absolutely Amazing!
This amp is a beast! A very loud beast! So happy I made the decision to purchase the modified series version. This is my first JCM 800 so I don't have anything to compare it to, but it sounds incredible. I'm running it through a Marshall 1960AX with Greenbacks.
Music background: I’ve been playing guitar for 29 years.
The enchanted edition of the classic metal weapon

JCM800 is the GOAT, rockers will never go wrong choosing it.

otherwise, there's nothing to criticize.

There are countless "British"-style guitar amplifiers out there, but take it from the lifelong guitarists and tone connoisseurs at Sweetwater, when it comes to Marshall tone, there's nothing like the real thing. We've played them all, from vintage JTM45s and the ultra-cool Plexi reissue to modern handmade masterpieces such as the JVM410. There isn't a model among them we can't recommend with total confidence, and that includes their more affordable models too, like MG, DSL, and Code series amps. Thanks to our tight relationship with Marshall, Sweetwater's always on the cutting edge of their latest designs, custom models, and limited-edition gems. If you want iconic tone from across the pond, you want Marshall, and your Sweetwater Sales Engineer will help you find the perfect one.