Boss TU-3 Chromatic Tuner pedal

The New World-Standard Tuner Has Arrived

The world's top-selling stage tuner, the Boss TU-2, evolves with the TU-3. Housed in Boss's tank-tough stompbox chassis, the TU-3 features a smooth 21-segment LED meter with High-Brightness mode that cuts through harsh outdoor glare. With Chromatic and Guitar/Bass tuning modes, Accu-Pitch visual verification, and support for 7-string guitars and 6-string basses, the TU-3 is the tuner no guitarist or bassist should be without.

Key Features

• 21-segment LED meter with brightness control
• High-Brightness mode for outdoor visibility
• Accurate to +/- 1 cent
• Accu-Pitch Sign function — visual confirmation when tuning is complete
• Chromatic and Guitar/Bass modes (supports 7-string guitar and 6-string bass)
• Guitar Flat mode for drop tunings up to 6 semitones below standard pitch
• Auto-mutes signal when tuner is active
• Powers up to 7 Boss compact pedals via DC OUT
• Buffered bypass
• Boss 5-year warranty

Tech Specs

• Tuning Range: C0 (16.35 Hz) – C8 (4,186 Hz)
• Reference Pitch: A4 = 436–445 Hz (1 Hz steps)
• Tuning Accuracy: +/- 1 cent
• Modes: Chromatic, Chromatic Flat ×2, Guitar, Guitar Flat ×2, Bass, Bass Flat ×3
• Display: Cent mode, Stream mode
• Bypass: Buffered
• Inputs: 1× INPUT jack
• Outputs: OUTPUT jack, BYPASS jack, DC OUT jack (powers up to 7 Boss pedals)
• Current Draw: 30mA (standard); 85mA (High-Brightness mode)
• Power: 9V battery (included) or AC adapter PSA series (sold separately)
• Battery Life: ~12 hrs (carbon-zinc); ~23.5 hrs (alkaline)
• Input Impedance: 1 MΩ
• Output Impedance: 1 kΩ
• Dimensions: 2-7/8" × 5-1/8" × 2-3/8"
• Weight: 390g / 14 oz (with battery)

Warranty: 5-year parts warranty; 90-day labor warranty. Check with Boss for full warranty details.