Boss TU3S Chromatic Tuner

Pro-Grade Tuning in a Compact, Always-On Design

The BOSS TU-3S delivers the trusted tuning accuracy and durability of the world-standard TU-3 in a streamlined, space-saving format. Compact and always active, it’s ideal for pedalboards where efficiency and reliability matter most.

Accurate, Visible, and Road-Ready

Featuring a 21-segment LED meter with adjustable brightness and High Brightness mode, the TU-3S ensures clear visibility in any lighting environment — from studio settings to outdoor stages. The Accu-Pitch Sign function provides a visual cue when tuning is precise, letting you dial in perfect pitch quickly and confidently.

Versatile and Player-Focused

With Chromatic and Guitar/Bass modes (including support for 7-string guitars and 6-string basses), plus a Guitar Flat mode for drop tunings up to six semitones, the TU-3S is built for modern players.

Power it via a BOSS PSA adapter, and use the DC Out jack to power up to seven additional BOSS pedals with an optional daisy-chain cable.

Specifications

• Compact version of the industry-standard TU-3

• 21-segment LED meter with brightness control

• Accu-Pitch Sign for visual tuning confirmation

• Chromatic, Guitar/Bass, and Flat tuning modes

• Supports 7-string guitars and 6-string basses

• Power: PSA adapter (DC Out for daisy chain)

• BOSS five-year warranty