Chromatic Tuner

Where to Buy

The New World-Standard Tuner Has Arrived

The world’s top-selling stage tuner, the BOSS TU-2, evolves and improves with the debut of the new TU-3. Housed in a tank-tough BOSS stompbox body, the TU-3 features a smooth 21-segment LED meter with a High-Brightness mode that cuts through the harshest outdoor glare. Choose between Chromatic or Guitar/Bass tuning modes, and enjoy visual pinpoint tuning verification with the Accu-Pitch Sign function. The TU-3 incorporates a convenient Note Name Indicator that can display notes of 7-string guitars and 6-string basses, while the Flat-Tuning mode can support up to six half-steps. It’s the new-standard tuner that no guitarist or bass player should be without!

Tuning Range
C0 (16.35Hz)–C8 (4186Hz)
Reference Pitch
A4=436–445 Hz (1Hz step)
Tuning Accuracy
±1 cent
Power Supply
DC 9 V: Dry battery 6F22 (9 V) type (carbon), Dry battery 6LR61 (9 V) type (alkaline), AC Adaptor (PSA series: optional)
Current Draw
30 mA (DC 9 V), 85 mA (DC 9 V, when High Brightness mode is on)
Owner’s Manual, Leaflet (“USING THE UNIT SAFELY,” “IMPORTANT NOTES,” and “Information”), Dry battery/9 V type (6F22)
AC adaptor: PSA series, Parallel DC cord: PCS-20A
Size and Weight
73 mm
2-7/8 inches
129 mm
5-1/8 inches
59 mm
2-3/8 inches
390 g
0 lbs. 14 oz.
In the interest of product improvement, the specifications and/or appearance of this unit are subject to change without prior notice.
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Brochures & Catalogs


If you have questions about operating your BOSS product, please check our Knowledge Base for answers to the most common questions.
You can also contact our Product Support department by phone or email.
In addition, we have a library of Owner’s Manuals and Support Documents that you can download and reference.

Owner’s Manuals