High-Precision DSP Tuner CG Suite / Pulsar

This guide covers the ultra-high precision acoustic tuner engineered specifically for the physical dynamics of classical guitars and acoustic string instruments—including initial attack pitch glide, natural string oscillation, and wound string harmonic properties.

Supported Applications

The full-featured tuner screen is available in Classical Guitar Suite (CG Suite) (handyman Tools > Tuner) and Pulsar Tuner (speed Tab).

Limitations in Lyra Score

Lyra Score does not include a standalone full-screen guitar tuner. Instead, it features a floating mini-tool (music_note icon) housing a wideband chromatic needle tuner (40 Hz to 2100 Hz) accommodating all instruments from double bass to flute. For strobe discs, perceptual snap, temperament optimization, and dyad beat tuning, please use Classical Guitar Suite (CG Suite) or Pulsar Tuner.

Layout & Automatic String Detection

When opening the tuner, microphone listening activates automatically. Pluck any single string, and the pitch detection engine (MPM: McLeod Pitch Method) automatically detects the target string (6th to 1st). You can also tap any number on the string selector to manually lock onto that string.

• 3-Color Hysteresis Feedback: Displays Blue when flat, Green when in tune (within ±1.5 cents), and Red when sharp. Smoothing filters and Schmitt trigger hysteresis eliminate rapid color flickering caused by micro-fluctuations in natural string vibration.
• All-String Tuning Checklist: Strings tuned in pitch receive a checkmark on the string selector, confirming full 6-string readiness at a glance.
• Header Settings: Change concert reference pitch (e.g., A4 = 440 Hz), switch input source (mic Built-in Mic / headphones Clip-on Mic), open detailed settings (tune), and view help (help_outline).

Figure: Main tuner interface (mode switcher, strobe disc / needle meter, and string selector)

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Three Tuning Operating Modes

Switch between three distinct operating modes from the top mode selector according to your rehearsal or stage situation.

1. Real-Time Mode (Needle Meter)

A continuous tracking mode utilizing an analog-style needle meter. Powered by a velocity-adaptive 1€ filter stabilizer, it delivers zero-lag agility while turning pegs rapidly and rock-solid needle settling when pitch stabilizes, providing an intuitive and direct tactile response.

2. Strobe Mode (±0.1 Cent Precision Strobe Disc)

An ultra-precision mode driven by an animated strobe disc synchronized to frequency difference ( $\Delta f$ [Hz] ).

• Reading Disc Rotation: Clockwise rotation indicates pitch is sharp; counter-clockwise rotation indicates pitch is flat. When pitch matches the target frequency, the pattern stops completely.
• Two-Stage Automatic Focus (Coarse to Fine): When pitch is far off (beyond ±35 cents), use the bottom needle bar for quick coarse tuning. Once pitch approaches the target and stabilizes, the strobe disc illuminates brightly, transitioning smoothly into sub-cent phase-vocoder precision tracking.

3. Auto Lock Mode (Perceptual Snap)

When a classical guitar string is plucked firmly, tension increases instantaneously causing a momentary upward pitch surge (attack glide) before decaying into its steady fundamental frequency. Auto Lock (Perceptual Snap) automatically tracks this decay curve, identifying the converged window that human ears perceive as musical pitch and locking the final cent readout.

1. Pluck a single open string and let it ring naturally.
2. Once initial attack turbulence stabilizes, a progress circle advances and automatically locks the needle at the steady pitch.
3. Choose from three capture window durations: Quick (300ms), Standard (600ms), or Precise (1200ms). Tapping the locked indicator (or pressing refresh) or plucking another string resets the lock for the next reading.

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Classical Guitar Temperament Optimization & Alternate Tunings

Configure temperaments and open-tuning presets from the bottom configuration panel.

Temperament Modes

• music_note Standard (12-TET): Standard equal temperament with 0.0 cent offset on all strings.
• auto_awesome Key Optimization: Select a key (E Major, A Major, D Major, A Minor, etc.) to apply micro-cent offsets that purify tonic and dominant 3rds and 5ths, eliminating common open-G string dissonances.
• grid_view Chord Voicing Optimization: Applies compensation offsets tailored for open low-position guitar chord voicings.

Alternate Tunings

Open the tune alternate tuning panel to select standard presets like Drop D (6th = D2), 6th=D & 5th=G, Lute Tuning (3rd = F#3), or save custom user tunings (bookmark).

Figure: Key/Chord temperament panel and Dyad Beat Tuning sheet

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Dyad Beat Tuning

An advanced tuning tool for fine-tuning harmonic beats after rough individual string tuning. Pluck two strings simultaneously (octaves, perfect 5ths, perfect 4ths, major 3rds) to evaluate beat interference frequency (Hz) visually and audibly.

1. Open Dyad Beat Tuning from the bottom temperament section or settings menu.
2. Select an interval pair (e.g., 6th string E2 and 4th string 2nd fret E3, 5th string A2 and 1st string E4, 3rd-2nd string major 3rd, or 5F-7F natural harmonics).
3. Pluck both notes together; the real-time beat rate (Hz) and deviation from target beat speed are displayed. Adjust your tuning peg until harmonic beating slows to a standstill.

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Tuner Settings Reference

Tap the tune icon in the top header to access detailed tuner configurations:

Figure: Tuner settings sheet (concert pitch, mic gain, needle snapping, strobe engine)

1. Concert Pitch (A4)

Adjust master tuning pitch A4 from 410.0 Hz to 450.0 Hz.

• Presets: Tap 415 Hz (Baroque pitch), 432 Hz, 440 Hz (standard guitar soloist reference), 442 Hz (orchestral/piano reference), or 444 Hz.
• 0.1 Hz Stepping: Use the slider or exposure_minus_1 / exposure_plus_1 buttons for precise ±0.1 Hz fine-tuning.

2. Microphone Input & Gain

Switch input source (Built-in Microphone or Clip-on / Piezo Pickup) and set pre-amplification gain.

• Auto (Mic Calibration): Evaluates background noise and 6th-string open sustain to calibrate the optimal gain level without digital clipping.
• Manual Presets: Adjust manually from Standard (1.0x) to Piezo / Contact (18x).

3. Auto Lock Sensitivity (Fast / Standard / Strict)

Adjusts how strictly the algorithm verifies pitch stabilization before snapping to a locked value.

• Fast: Snaps quickly on initial pitch stabilization. Best for quick re-tuning between rehearsal pieces.
• Standard (Recommended): Balanced responsiveness and measurement accuracy.
• Strict: Waits until all string flutter settles. Ideal for recording sessions and new string evaluations.

4. Needle Snapping / Cent Snapping (OFF / Soft / Standard / Strong)

Natural classical guitar strings exhibit slight micro-modulations (±1 cent) even when perfectly in tune. This setting stabilizes the needle around center (0 cent).

• OFF: True linear needle tracking with zero magnetic pull.
• Soft (±0.5c) / Standard (±1.5c) / Strong (±3.0c): Smoothly steadies the needle within the specified threshold.

5. Strobe Engine (MPM / IQ Phase Lock)

Selects the core DSP algorithm driving strobe disc rotation.

• MPM (Standard · High Stability): Resilient against heavy 2nd harmonics on wound bass strings (4th-6th).
• IQ Phase Lock (High Resolution): Heterodyne IQ demodulation tracking phase angles down to sub-cent beat resolution.

6. Pitch Ribbon Graph (ON / OFF)

Displays a rolling timeline showing pitch variations over the last several seconds, letting you visualize attack glide curves.

7. Smart Dynamic Zoom (ON / OFF)

Automatically zooms into the meter and pitch ribbon scale when pitch nears center, expanding resolution for the final 1–2 cent peg adjustment.

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Guitar Profile Association & Tuning Logs CG Suite Only

Using the tuner inside Classical Guitar Suite (CG Suite) unlocks profile integration:

• Active Guitar Selector: Tapping the guitar card (music_note displaying guitar model and scale length in mm) applies scale-length compensation (e.g., 650mm, 640mm, 630mm) tailored to your instrument's string tension curve.
• Tuning History & Trend Graphs: Each time you confirm pitch in Auto Lock mode, the reading is logged to your active guitar's current string set, plotting restringing elongation stability and aging degradation over time.

Limitations in Pulsar Tuner

As a standalone lightweight utility without a cloud database, Pulsar Tuner does not store long-term tuning trend histories or link to guitar profile databases. All real-time, strobe, auto lock, temperament, and dyad tuning algorithms operate with identical acoustic precision.