MXR M400 Turbo Tuner

MXR Turbo Tuner

The MXR Turbo Tuner combines the legendary precision of the Sonic Research Turbo Tuner with the rugged reliability and versatility of MXR pedals. Developed around the original Sonic Research tuning engine, this professional-grade strobe tuner delivers exceptional ±0.02-cent accuracy for fast, reliable tuning on stage, in the studio, or at home.

Its real-time strobe display responds instantly to pitch changes, making accurate tuning intuitive for players of all experience levels. Five customizable presets support instruments with up to 12 strings and alternate tunings with offsets of up to ±50 cents.

Four adjustable brightness levels ensure excellent visibility in different lighting conditions, while selectable true or buffered bypass provides flexibility for any pedalboard setup. Additional features include a 9V DC passthrough output to power another pedal and a USB-C connection for firmware updates and future editor software.

Features

• Professional-grade strobe tuner based on the acclaimed Sonic Research Turbo Tuner engine

• Personally engineered by Sonic Research founder Roger Schlichting

• Exceptional ±0.02-cent tuning accuracy

• Responsive real-time strobe display for fast, precise tuning

• Five customizable presets supporting up to 12 strings

• Adjustable tuning offsets of up to ±50 cents

• Four display brightness levels for excellent visibility

• Selectable true bypass or buffered bypass with three buffered submodes

• 9V DC passthrough output for powering an additional pedal

• USB-C connectivity for firmware updates and upcoming editor software

• Rugged, pedalboard-friendly MXR construction

Specifications

• Tuning Range: C0 (16.35 Hz) to C8 (4,186.0 Hz)

• Accuracy: ±0.02 cents (calibrated crystal oscillator)

• Reference Pitch: A4 = 300.0 Hz to 599.9 Hz, adjustable in 0.1 Hz increments

• Presets: 5 customizable presets

• String Support: Up to 12 strings

• Tuning Offsets: ±50 cents

• Display Brightness: 4 adjustable levels

• Bypass: True Bypass / Buffered Bypass (internal switch selectable)

• Connections: 1/4" Input, 1/4" Output, 9V DC Input, 9V DC Output, USB-C

• Power Supply: 9V DC

• Current Draw: 48 mA (minimum brightness) to 73 mA (maximum brightness), typical

• Dimensions: 4.4" × 2.4" × 1.9" (11.2 × 6.1 × 4.8 cm), H × W × D

• Weight: 6.8 oz (192 g), without battery