Boss ML-2 Guitar Effect

Boss ML-2 Metal Core — Extreme High-Gain Distortion Pedal

The Boss ML-2 Metal Core is the most potent and heavy distortion pedal ever created by BOSS, packing extreme gain into a single stompbox. It delivers massive distortion and heavy lows for nu-metal, grindcore, industrial, hardcore, and death metal. Ferocious and biting tone allows this instrument to cut through any blast beats the rhythm section creates, making it a natural choice for down-tuned guitars and palm-muted chugging riffs.

What Sets the ML-2 Apart in the BOSS Lineup

Unlike the mid-scooped MT-2 Metal Zone, this pedal is voiced for modern high-gain metal with a tighter character suited to 7-string guitars and dropped tunings. Its LOW and HIGH EQ knobs are boost-only, letting players stack extra low-end weight or top-end bite on top of an amp's natural voicing. An integrated noise gate keeps the signal quiet even at maximum gain settings, making it one of the cleanest high-gain pedals in the BOSS compact lineup.

Signal Path and Connectivity

The signal chain uses a single mono input and mono output, designed to slot into any standard guitar rig. Buffered bypass keeps the tone intact when the pedal is off, which matters for long cable runs and complex pedalboards. The unit runs on a 9V alkaline battery or an optional PSA-series AC adaptor.

• Type: Distortion — analog high-gain circuit for modern metal
• Connections feature 1 x 1/4" mono in (1 M ohm) and 1 x 1/4" mono out (1 k ohm).
• Bypass: Buffered (not true bypass) — preserves tone when disengaged

EQ and Gain Controls

The four-knob layout gives direct access to the pedal's core voicing without menus or hidden parameters. Overall gain is set by the DIST knob, while the LOW and HIGH knobs form a 2-band boost-only EQ for adding weight or bite. The LEVEL knob balances the pedal against a clean rhythm tone or another overdriven stage.

• Distortion: DIST knob — sets gain from heavy rhythm to searing lead
• EQ: 2-band boost-only (LOW and HIGH) — adds low-end weight or metallic top end
• Level: LEVEL knob — matches output volume to the rest of the rig

Power, Build, and Pedalboard Footprint

The ML-2 runs on a single 9V battery or a PSA-series AC adaptor, drawing 60 mA with an expected battery life of around 5.5 hours under continuous use. The CHECK indicator doubles as a battery check, so players always know the power status mid-set. Measuring 73 x 129 x 59 mm and weighing 420 g with a battery installed, the chassis fits any standard pedalboard layout.

• Power Supply: 9V alkaline battery (6LR61) or PSA-series AC adaptor (sold separately)
• Current Draw: 60 mA — battery life approx. 5.5 hours continuous use
• Dimensions and Weight: 73 x 129 x 59 mm, 420 g (with battery)
• Construction: Road-tough BOSS metal chassis with five-year warranty