Vivaldi Keyboard

Play piano in 22 historical temperaments, transpose for 21 instruments, import your own SoundFonts. Now playable from any Bluetooth keyboard on iPad and Mac.

Vivaldi Keyboard turns your iPad or Mac into a true-pitch keyboard for studying historical temperaments, playing transposing instruments, and hearing how intonation actually sounds.

TEMPERAMENTS • 22 temperaments in 7 families — Equal (12-TET); Just Intonation (5-limit, 7-limit); Meantone (1/4, 1/3, 1/5, 1/6 and 2/7 comma); Well Temperament (Werckmeister III, Kirnberger III, Vallotti, Young, Neidhardt, Barnes); Historical (Bach/Lehman, Rameau, Kellner); Pythagorean; Extended (19-TET, 31-TET, 53-TET, Arabic 24-TET) • Live cent deviation panel — see the exact offset of every note from Equal Temperament • Variable tonic for non-equal temperaments: decide which keys are pure and which are tempered • Interactive guide with a description of every temperament

TRANSPOSING INSTRUMENTS • 21 instruments with verified MIDI range and octave transposition: saxophones (soprano, alto, tenor, baritone), clarinets (Bb, Eb), trumpets (Bb, C), horn in F, trombone, tuba, flugelhorn, flute, piccolo, oboe, bassoon, violin, viola, cello, double bass • The keyboard dims the keys outside your instrument's written range, so you always see what is playable • Frequencies are transposed to real concert pitch — play a written C on alto sax, hear the actual Eb concert at the correct frequency for the chosen temperament • Pitch updates live when you change instrument or temperament mid-performance

SOUNDS Two modes, switchable in Settings: • Real-time synthesis — 6 built-in timbres: Piano, Organ, Flute, Strings, Harpsichord, Bell • SoundFont playback — FluidR3 GM (142 MB) bundled, with 4 free preset as a taste of the full library: Honky-Tonk Piano, Drawbar Organ, Violin, Trumpet Multi-touch polyphony on iPad, click-and-drag glissando on Mac.

REFERENCE FREQUENCY • A4 configurable from 415 Hz (baroque) to 466 Hz, 1 Hz steps • 440 Hz modern standard as default

INTERFACE • Steampunk design with rotating mechanical wheels for every control • 88-key piano with zoom and horizontal scroll • Italian and English

PRO UPGRADE — optional one-time €1.99, Universal Purchase iPad + Mac • Unlock the full FluidR3 GM library: all 128 General MIDI programs plus drum kits, organized by instrument family • Import your own .sf2 SoundFont files for unlimited custom sounds

No ads, no subscriptions, no data collected.

For musicians, transposing instrument players, music theory teachers, tuners, choir directors, baroque performers, and anyone curious about how music sounded before equal temperament.

Available for iPad and Mac. Not available on iPhone.