AS Music Theory (So Far): Concepts, Tools and Spaced Repetition

It has been a busy few weeks. AS Music Theory is a new web application to aid music theory learning and understanding. In a short time, it has gone from an idea to a working site with a library of interactive lessons, a set of hands-on practice tools, and a learning system that quietly schedules your revision for you. This post is a tour of what is here now and how the pieces fit together.

The big idea: learn it, then play it

Everything on the site is built around one idea: music theory sticks when you can hear it and play it, not just read about it. So the site is split into two halves:

• Concepts teach one idea at a time, interactively.
• Tools are open-ended instruments for your own practice and tinkering.

Underneath both sits a spaced repetition system that decides what you should revise and when. More on that below.

The Concepts library

Each concept is a short, focused lesson built around an on-screen piano. You read a little, then you press keys, and the idea becomes something you can hear. The library is organised into three groups.

Fundamentals starts from first principles:

• Notes & the Keyboard: how every key maps to a pitch, and why the black keys carry two names.
• Understanding Sound: Pitch and Amplitude: sweep an oscillator across the audible range to hear how frequency makes pitch and amplitude makes loudness.
• Musical Notes: the twelve notes as music's alphabet.
• Reading Music, in four parts: the stave and clefs, note values and rhythm, time signatures and bars (with a metronome you can hear counting the pulse), and dynamics, tempo and articulation.

Harmony builds on those foundations:

• Intervals: play a pair of notes and have the gap named, or pick an interval to hear it.
• Chords: press a chord to hear it, or play your own and have it identified.
• Scales: pick a tonic and a scale type, the seven modes plus the minors, and play it up and down.
• Key Signatures: the circle of fifths, and why D major needs F sharp and C sharp.
• Chords in a Key: the diatonic seven with Roman numerals, so you can find out whether the chord you just played is the I, the V, or an outsider borrowed from elsewhere.

Key Terms rounds things out with short reference definitions of the words the other lessons lean on: root, tonic, diatonic, consonance and dissonance, inversion, voicing, transposition and more, plus a glossary.

One keyboard, four ways to play it

The piano that runs through all of this can be played however suits you: click or drag with the mouse, tap with multiple fingers on a touch screen, use a two-row layout on your computer keyboard, or plug in a real MIDI keyboard. MIDI support includes chords, velocity (how hard you play changes the loudness) and the sustain pedal, so a controller like a MIDI keyboard works just as you would expect.

The Tools

The Tools section is where you put theory to work. Four tools have landed in the last few weeks:

Piano Roll. Record what you play, see it as a scrolling piano roll or on the staff, and play it back. You can save your sketches, loop a passage, set a tempo and key, upload an existing MIDI file to view and play, and export your work to MIDI.

Ear Training. A note sounds and you find it on the keyboard by ear, with higher and lower hints to guide you. Drills cover intervals, notes within a key, absolute pitch and pitch classes, so there is a level whether you are just starting or chasing something harder.

Scale Practice. Drill every scale from every root in three ways: play it on the keyboard, spell it note by note, and recognise it by ear. The modes and the harmonic and melodic minors are all in there.

Sight Reading. Read a four-bar excerpt on the staff and play it back on the keyboard. Your notes turn green when right and pink when wrong, and the exercises run across easy, moderate and advanced tiers.

Spaced repetition: the system that helps you retain what you learn

Learning something once is easy. Still knowing it weeks later is the hard part, and that is the problem the spaced repetition system is built to solve.

The principle is simple. After you review something, you tell the app how well you remembered it. Things you find hard come back soon; things you know well come back less and less often, stretching out over days and weeks. Reviewing something just before you would have forgotten it is what moves it into long-term memory with the least effort, and the expanding schedule aims you at exactly that moment. Under the hood it is a variant of the well-proven SM-2 algorithm, the same family of scheduler used by classic flashcard apps, with the schedule computed server-side and tied to your account.

Here is how it shows up across the site:

Every concept has a Test tab. Alongside the lesson, each concept's key points are turned into flashcards. You read the question, recall the answer, reveal it, then rate yourself Again, Hard, Good or Easy. That rating is all the scheduler needs. Some cards are interactive, asking you to type an answer or play you an example, but the self-rating is always what drives the schedule.

There is a global Review area. Rather than visiting concepts one by one, the Review page pools the due cards from every concept into a single queue, leading with whatever you are closest to forgetting. It is the fastest way to do a daily review. If nothing is due, you are caught up, and you can still press Practice anyway to run through a deck without affecting your schedule.

You can add your own cards. On any concept's Test tab (or from the Review area) you can write your own question and answer, and your cards are mixed into reviews alongside the built-in ones. They are private to you, and you can edit or delete them any time.

The practice tools feed it too. Scale Practice and Sight Reading plug into the same scheduler. Sign in, and the scales you struggle to spell or the excerpts you misread come back sooner, while the ones you nail recede into the background. Your practice time goes where it is actually needed.

You can try any deck while signed out, but nothing is saved, so the spacing cannot carry over to your next visit. Signing in is what lets the schedule do its job across days.

What's next

We've started with the concepts library, the four tools, and the learning system that ties them together. There is plenty more planned, and updates will be posted here as they land. In the meantime, head to asmusictheory.com, open a concept, and press some keys!