Variables is a free music-theory companion. It turns the parameters behind every piece of music — pitch, duration, dynamics, timbre, tempo, harmony, texture and form — into clear explanations, tables and tools you can use while you practise.
WHO IT IS FOR
Students, producers, guitarists, pianists and anyone who wants to understand music in numbers as well as notes. No account, no in-app purchases and no internet connection is required to use the lessons, quiz or calculator.
WHAT YOU CAN DO
Core variables
Open any of the eight musical parameters to see its unit, typical range, how it is written on a score and a practical example. Change one of them and the music changes.
Scales and harmony
Browse interval sizes in semitones and just ratios, eleven scale formulas (major, minor, modes, pentatonic, blues, whole-tone, chromatic) and ten common chord shapes stacked from the root.
Rhythm and tempo
See note values in quarter-note beats, Italian tempo markings with BPM ranges, and time signatures from 4/4 and 3/4 to 5/4 and 7/8.
Calculator
Enter a tempo to convert every common note length into milliseconds and hertz — including dotted notes and triplets — for delays, LFOs and click tracks. Pick a note name, octave and A4 reference to get frequency, MIDI number and period using equal temperament.
Quiz
Fourteen questions covering pitch, tempo, scales, harmony, dynamics, texture and rhythm. Each answer shows a short explanation. Retake as often as you like.
WHY “VARIABLES”
Music is often taught as names and symbols. This app treats the same ideas as measurable quantities: hertz, beats, cents, semitones and BPM. The goal is a reference you can open next to a DAW or a score, not a social network and not a streaming service.
PERMISSIONS
Internet access is used only if the device is online. All lesson content, the quiz and the calculator work offline.
Variables is an independent educational app. It is not affiliated with any instrument brand, school or streaming platform.
Support: contact the developer through the email listed on this Play Store page.
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