What tubes does the Marshall JCM900 2500 / 4500 use?

The Marshall JCM900 2500 / 4500 uses 3× ECC83 preamp tubes and 2× EL34 power tubes.

When was the Marshall JCM900 2500 / 4500 produced?

The Marshall JCM900 2500 / 4500 was produced 1990–2000.

Marshall JCM900 2500 / 4500 preset

Verified · 85/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

These are the 50-watt JCM900 heads. The drawings cover the 2500-series Master Volume models and share the power amp with the 4500-series Dual Reverb. The Master Volume preamp uses two ECC83s with diode clipping, two gain ranges and footswitchable A/B master volumes. An ECC83 inverter drives a pair of EL34s with a High/Low output power switch, and there are record and direct outputs.

Years produced: 1990–2000
Made in: UK
Wattage: 50W
Channels: 1
Preamp tubes: 3× ECC83
Power tubes: 2× EL34

Tags: british, crunch, high-gain, el34, mid-wattage.

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