The MXR® Smart Gate® M135 is a precision noise gate designed to eliminate hiss, buzz, and amplifier noise without sacrificing your tone or dynamic expression. With three selectable noise reduction ranges—Hiss, Mid, and Full—the Smart Gate intelligently suppresses unwanted noise while preserving picking transients, sustain, and subtle playing details.

Its advanced circuitry reacts gradually to long notes and quickly to tight, syncopated playing, ensuring the most natural performance possible. Ideal for taming high-gain amps, long pedal chains, or noisy environments.

• Three selectable types of noise reduction: Hiss, Mid, and Full
• Intelligent gating preserves sustain and playing nuances
• Fast attack time keeps picking transients intact
• Hardwire bypass for maximum signal integrity
• Precise threshold trigger with gate status LED
• Clean, quiet circuitry suitable for stage and studio
• Compatible with 9V battery or standard power supplies

• HI TRIGGER RANGE Switch: Extends trigger sensitivity for extremely noisy setups
• TRIGGER LEVEL Knob: Adjusts gate threshold sensitivity (indicated by yellow GATE LED)
• NOISE BAND CUT Switch: Select Hiss, Mid, or Full noise reduction
• Footswitch: Activates effect (red LED indicates ON)

• Connect your guitar to the INPUT jack and your amp to the OUTPUT.
• Start with TRIGGER LEVEL fully counterclockwise.
• Select noise range: Hiss (highs), Mid (mids), Full (lows).
• Activate the pedal and play a note, allowing it to ring out.
• Raise TRIGGER LEVEL until noise is effectively reduced.

• Input Impedance: 1 MΩ
• Output Impedance: 1 kΩ
• Max Input Level: +7 dBV
• Max Output Level: +7 dBV
• Noise Floor (Gate Closed): -105 dBV
• Noise Floor (Gate Open): Hiss -100 dBV, Mid -100 dBV, Full -96 dBV
• Frequency Response: 20 Hz–20 kHz (Gate Open)
• Bypass: Hardwire
• Current Draw: 15 mA
• Power: 9V battery or 9V DC supply (ECB003 or Iso-Brick compatible)

Each mode is optimized for different noise sources:

• Hiss: Best for high-frequency noise such as keyboards, vocal mics, wind instruments, bass, or high-gain treble-heavy guitars.
• Mid: Ideal for distorted guitars, harmonicas, and midrange-boosted sources.
• Full: Best for low-end hum, AC noise, display interference, or grounding issues.

For maximum noise reduction on large pedalboards, place the Smart Gate last in the signal chain before the amplifier.