KORG GT-4 - High-performance compact tuner for guitar and bass (Strobe, Mirror, and Meter modes)

KORG GT-4 - High-performance compact tuner for guitar and bass (Strobe, Mirror, and Meter modes)

The KORG GT-4 is a handheld guitar and bass tuner with exceptional visibility and professional-grade accuracy. Its unique circular display with red LEDs and a large central note display makes it easy to read in any situation, from the studio to the stage. It features three display modes—Strobe, Mirror, and Meter—so you can choose the tuning style that's most comfortable for you, plus a "low fifth" (flat) function for tuning down by up to 5 semitones. It's compatible with 7-string guitars and up to 6-string basses, features an internal microphone for acoustic instruments, and offers ±1 cent accuracy with automatic power off to conserve battery life.

Main features

• Three tuning modes: Strobe, Mirror and Meter, with clear and stable reading on the LED ring and the note in the center.
• “Flat” function: tunings lowered from 1 to 5 semitones , ideal for Drop D, C, B and heavier settings.
• Extended Compatibility: Recognizes 7-string guitar (including 7B) and 6-string bass (Low B / High C), with automatic note detection.
• Built-in microphone for wireless acoustic tuning; 1/4" INPUT jack for signal (connecting a cable deactivates the microphone).
• High precision: detection accuracy better than ±1 cent .
• Reference calibration A4: Adjust between 432–448 Hz in 2 Hz steps (indicators on the ring).
• Power Saving: Auto-off after ~10 minutes of no input; in Strobe mode, the LEDs dim if there is no signal (~30 s) to extend battery life.
• Portable and robust: powered by 2 AAA batteries (battery life approx. 18 hours), ultra-compact size and light weight.

Product benefits

• Instant readability in any environment: The circular LED ring provides a highly visible reference even in low light or from awkward angles.
• True instrument and tuning versatility: covers everything from standard electrics to 7-string and 5/6-string basses, including common rock and metal bass tunings.
• Accuracy and consistency: ±1 cent and visual modes help you fine-tune quickly and easily, reducing time between songs or takes.
• Acoustic-ready: The built-in microphone allows for tuning without connecting cables; it also supports an optional contact microphone.
• Designed for live performance: auto-shutoff and LED dimming to maximize battery life during long gigs and rehearsals.

Use cases

• Stage: Strobe mode for quick, fine adjustments between tracks, with excellent visibility.
• Noisy rehearsal: Use the jack input or a contact microphone to isolate yourself from ambient noise.
• Classes and studio: Meter/Mirror mode for students and recording sessions that require a clear and stable reference.
• Low Tunings: Set Flat up to -5 semitones for Drop C/Drop B or Baritone tunings.

Frequently Asked Questions

• Does it work for acoustic guitars? Yes, thanks to the built-in microphone ; you can also use the jack input or a contact microphone.
• Can I use it with a 7-string or 6-string bass? Yes, it recognizes 7B on guitar and Low B/High C on bass.
• Does it have A4 calibration? Yes, with indicators for 432–448 Hz in 2 Hz steps.
• Does it save battery life? Yes, it dims the LED ring without a signal and turns off automatically after about 10 minutes without input.

Description for projects

KORG GT-4 guitar/bass tuner with Strobe, Mirror, and Meter modes; Flat function -1 to -5 semitones; accuracy ±1 cent; detection for guitar (B1–B6) and bass (Low B–High C); built-in microphone and 1/4” mono input; auto power off; 2xAAA power supply; dimensions 61 × 65 × 22 mm; weight 67 g; A4 reference calibration marked 432–448 Hz (2 Hz steps).