Capturing the raw power and searing crunch of the legendary vertical-input 2203/2204 heads, the Synergy Marshall JCM 800 Preamp Module delivers authentic British tube tone directly to any Synergy hardware dock. Driven by three 12AX7 preamp tubes, this patented interchangeable module incorporates an integrated 0-watt power amp and phase inverter section to replicate real dynamic power-amp sag and response. Its dual-channel layout features independent Preamp, Master Volume, Bass, Middle, Treble, and Presence controls per channel, alongside 3-position Bright switches and a High/Low Input toggle to mirror original JCM 800 input behavior. An internal PCB Cathode Select switch provides fine-tuned tube voicing for unmatched high-gain crunch and explosive lead sustain.

Few amplifiers have achieved the near mythic status of the Marshall JCM 800. When it first roared to life in the early 1980s, it didn’t just define an era – it ignited it. Kicking off a new generation of tones, the JCM 800 became the definitive voice of hard rock and heavy metal. Big, aggressive, and unmistakably British. It took the foundational crunch of the Plexi and added the gain, punch, and focus that powered a generation of guitar heroes.

Marshall JCM 800 2203 (100w) and 2204 (50w) circuits, with their single channel, cascaded gain stages, and signature midrange roar, delivered a level of authority and articulation that set them apart from anything before or since. It was the perfect balance of power and precision. For countless players, the JCM 800 isn’t just an amplifier – it is the amplifier.

Now, Synergy and Marshall have teamed up once again to bring you, for the first time ever, this legend in a three-tube, dual-channel preamp module. Utilizing Marshall’s original circuit design, the JCM 800 module delivers the raw energy, attack, and articulate overdrive of the iconic vertical-input 2203/2204 amplifiers. Whether you’re chasing the three-dimensional crunch of 80s rock or crushing tight gain for modern metal, the JCM 800 module gives you the legendary tonal experience that defined a generation.

Authentic three-tube preamp based on the legendary Marshall JCM 800 (2203 / 2204 Vertical Input)

3 x 12AX7 preamp tubes for full harmonic complexity and dynamic response

Built-in 0-watt power amp and phase inverter for true amp-like feel

Two identical channels, each with: Preamp, Bass, Middle, Treble, Presence

Independent Master Volumes for rhythm/lead

Bright switch (three-position) adjusts bright cap value for tone shaping

High/Low Input switch replicates original JCM 800 input behavior

Cathode Select switch on PCB for adjustable tube response

Easy to install and remove from Synergy preamp docks

Synergy hardware and interchangeable preamps are protected under US patent.

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