BIGZUN TUNER – Chromatic Tuner, 4HP Eurorack Module (assembled and tested)

TUNER is a 4HP chromatic tuner for Eurorack. Patch in any audio signal and it shows the note, the octave, the deviation in cents and the exact frequency in hertz – crystal-clocked, with 0.01 cent resolution. A passive THRU jack keeps it in your signal path, REF gives you a reference tone for tuning by ear, and AUX outputs an in-tune gate or a sub-octave.

Features

• Note, octave, cents and Hz on a 0.91" OLED
• Five display views: classic bar, strobe, big digits, needle, minimal
• Crystal-clocked measurement, 0.01 cent resolution, 20 Hz – 5 kHz
• Harmonic-proof: extra zero crossings are ignored, no octave jumps
• THRU – passive copy of the input
• REF – crystal reference tone, C1 to B7
• AUX – in-tune gate or a square wave one octave below the input
• Any reference pitch: A4 from 430 to 450 Hz in 0.5 Hz steps (432, 440, 442, 443 …) – display and REF tone follow
• Menu: tolerance 1–10 cents, calibration ±100 ppm, settings saved automatically

Use cases

• Tuning VCOs and complete synth voices
• Calibrating 1V/oct tracking
• Checking the drift of analogue oscillators
• Tuning by ear against a reference tone
• A permanent tuner in a live or studio case
• Gating envelopes when a note is in tune, or adding a sub-octave to any oscillator

Technical specifications

• Format: Eurorack 3U, width 4HP
• Depth: approx. 20 mm
• Power: +12 V only, approx. 40 mA (10-pin power cable included)
• Microcontroller: CH32V003 with crystal, comparator input stage
• Jacks: IN, THRU, REF, AUX
• Controls: ▼ / ▲ buttons, MENU button
• Black front panel with white labeling

In the box

• TUNER module – fully assembled and tested
• Eurorack power cable

Shipping

Handmade in Poland. Securely packed and dispatched within 1–2 working days with tracking.