Microtonal & just intonation MIDI editor — DonutStudio

Harmonies are relationships

Click a hotspot to see what each interaction does on the piano roll.

• Shift-click to link — Pick a master, pick a slave. The slave's frequency becomes a pure ratio of the master: 3:2 for a fifth, 5:4 for a major third, 7:4 for a harmonic seventh.
• Double-click to cycle — Step a link through the harmonic series. From H1, H3, H5, H7, all the way to H32, every interval from the overtone series is one click away.
• Dynamic hierarchies — Any note can be master and slave at once. A → B, B → C, C → D, and the whole graph resolves in real time.
• Move the anchor — Transpose a root and every dependent note cascades along, preserving every relationship. The graph just follows.

The full tension spectrum

DonutStudio gives you the widest range of harmonic tension, from absolute consonance (zero beating, pure fusion) to extreme dissonance (collisions between different harmonic anchors that create beating patterns like Balinese gamelan), including intervals the ear has no template for. The harmonic series is a space to explore. Every ratio is a creative choice, and the composer is the one who arbitrates.

Chord tools that understand harmony

DonutStudio's chord tools work with pure ratios and harmonic relationships, so a detected chord is a structure of intervals.

Tune every note exactly, or let a scale do it

Links are one way to place a pitch. Sometimes you want the number. Microtune any note by an exact cents offset, or mark it as a tuning root and let the rest of the graph resolve around it, all independent of the 12-TET grid underneath.

Draw the pitch of every note

Every note carries an editable pitch curve. Open the expression editor and shape per-note pitch-bend points by hand, with tension and S-curve controls on every segment. Draw natural vibrato, scoops, microtonal slides, and vocal-style portamento directly on the roll. Generate a vibrato curve from depth/rate/shape, then refine it point by point, or freeze the sections you've dialed in so later edits leave them alone.

30+ transforms, from quantize to euclidean rhythm machines

Apply across selections, individual tracks, or the whole project. Every transform respects harmonic links and is fully undoable. Hold Shift while you pick one to open the per-chord overlay. Dial in different parameters for each chord in your selection and apply them all in a single pass.

Timing & rhythm

• Quantize — Snap notes to grid
• Legato — Extend per-pitch to fill gaps
• Staccato — Shorten notes by factor
• Reverse — Mirror positions in time
• Humanize — Random timing & velocity nudges
• Double length — Scale position + duration ×2
• Halve length — Scale position + duration ÷2
• Arpeggio — Spread chord notes across time with shape, span, and direction controls
• Strum — Stagger chord starts like a strum, S-curve sweep with adjustable timing
• Euclidean — Distribute hits evenly using Euclidean rhythm patterns
• Ratchet — Subdivide a note into rapid repeats
• Flam — Add grace-note offsets for a flammed attack
• Ghost — Drop in low-velocity ghost notes around the beat
• Groove — Apply swing/groove templates to the selection
• Riff machine — Generate riffs and patterns over the selection

Harmony & linking

• Auto Tune — Smart chord grouping retunes selection to pure JI ratios
• Auto Link — Link selected notes to the hovered master in one shortcut
• Chain Masters — Wire masters together end-to-end into a single hierarchy
• Chain Retune — Walk a master chain and re-resolve every dependent note

Pitch & expression

• Transpose — Shift selection by ± semitones
• Voicing Spread — Distribute pitch classes across octaves at a target interval
• Vibrato — Generate pitch-bend curves with depth, rate, and shape
• Draw Pitch — Hand-draw the F0 contour directly on a note
• Erase Pitch — Wipe user pitch edits, restore the source curve
• Freeze Pitch — Lock specific sections of the pitch curve so other edits don't disturb them
• Bake Pitch to Points — Convert a continuous pitch curve into editable breakpoints
• Load Rendered Pitch — Pull the rendered F0 from a vocal render back as edit data

Note management

• Consolidate — Merge overlapping fragments into single clean notes
• Split Notes — Break a long note into N equal pieces
• Merge Notes — Join adjacent notes of the same pitch into one
• Generative — Algorithmic note generation across a selection
• Mute — Toggle muted state on the selection
• Set Track — Move selection to another track (0–15)
• Consolidate Sample — Render attached audio with all transformations into a clean WAV

Velocity

• Set Velocity — Absolute value across selection
• Scale Velocity — Multiply current velocity by a factor

Vocal-specific

• Split Sentence — Split multi-word lyric notes into one note per word — equal, syllable, or phoneme distribution
• Fill Lyrics — Auto-distribute a lyric block across selected notes