The guide

Overdub is a studio for you and your agents. You lay down a take, your agent plays over it, you play over that, and every take is signed: warm for you, cool for it. This page gets you from the door to a kept take in five minutes, then shows where everything else lives. In the studio, ? shows every key.

Your first overdub in five minutes

1. Open the studio. overdubstudio.com/app/ in Chrome, Safari or Firefox, on a computer or a phone. Nothing to install, no account. It opens on Night Shift; the Song menu's Demos has three more, in other genres. The first time, a small card called Take one walks you through the steps below. It waits for each one to really happen, and you can close it. It stays out of songs someone sends you, and closing it puts back the loop it set, unless you've changed that loop since.
2. Hear it. Press Space (on a phone, ▶ at the top). Warm parts were played by a person, cool ones by an agent.

3. Lay down take one. Open the Sketch tab and pick a way in:

   • Hum it. H turns the mic on (the browser asks first) and H again stops. The notes are written as you go, as you sang them. Once the song has a key (one you set, or a part in one; a beat alone doesn't give it one), notes between keys move into it, and it says how many ("Moved 2 notes into A minor"), with Undo.
   • Tap it. T, then F J K L for kick, snare, hat and open hat. The pads work too.
   • Play it. ` turns on musical typing (A S D… are the white keys), or plug in a MIDI keyboard. Musical typing and a phone's keys have two helpers, on until you turn them off: what you play lands on the grid, and the keys play only the song's key. The line over the keys says so: Snapping to 1/16, in C minor. Click either part to turn it off, and it says what you get instead (Your timing, every note); click it again to turn it back on. This browser remembers. With no key set, it says what the keys play instead (in C major). A MIDI keyboard's notes stay as you play them.

   Capture is always on. Everything you hum, tap or play lands in the Takes list, so nothing is lost.

4. Keep it. Keep as a clip in Sketch, or Keep on the take in the Takes list. It lands on a track, signed by you. Band on a kept take (or ⇧B on a selected clip) builds chords, bass and drums around it in a style you pick, on new tracks; your notes stay as they are, and one undo takes the band back.
5. Ask the agent for a take. Open the Agent tab (A; ⌘/ or Ctrl+/ to type) and ask for something over it: "Give me a bassline under this." No key? Press Try the demo agent (no key), or just type: what you type stays in the box, and Ask the demo agent sends it. The demo agent is a scripted session, not a live model, but it uses the real tools, so everything it does is signed and undoable. It answers what it can, and when something is past its script it says so first, then offers the nearest thing it can on the part and bars you named.
6. Keep one. Its takes arrive as cards. Hold to hear plays one over yours; let go to go back. Keep the one you like.

That's an overdub. Take one is yours, take two is the agent's, and the History tab shows both, with the reason the agent gave. ⌘Z undoes the latest edit. Revert all Claude's changes (keep mine) takes back everything the agent did and leaves your edits alone, and ⇧⌘Z puts it back, as it does after Undo on one of the agent's lines there.

Record into the song

Select a track and press R (on a phone, the ● at the top). Beside the record key the top bar says where it goes (Onto Bass; a click there picks another track), and the track stays the target until you select or arm another: a click on empty space to move the marker doesn't change it. In Hum it, Onto names the track your hum goes onto: a hum never goes onto a drum track unless you armed it, so with Drums selected it says Bass (or new track). It records from the start marker, after one bar of count-in: the bar before the marker plays with the click (below bar 1, the click alone), the position counts −1.4 to −1.1 in red, and a big numeral over the track counts 4 3 2 1. R or Space during the count calls it off. With the song already playing, R waits for the next bar line and counts the beats left in this one. Then whatever you play, tap or hum lands on that track at the bars where you played it; musical typing and a phone's keys are snapped as they record, as the line over the keys says. Space stops and keeps the take; R again punches out and the song plays on; ⌘Z takes it back out.

• Watch the ball. Beside the position, a cell for each beat of the bar and a square that travels between them, landing on each beat as you hear it, so you can see the next one coming with the sound off. It goes red while a take counts in and records.
• The click. A take clicks even with the click off: that's While recording in the options under the caret beside Click, on until you turn it off. K turns the click on and off for everything, ⇧K steps the count-in through 1 bar, 2 bars and off, and the options have the level too. They stay set in this browser. The click is never in the mix or an export.
• Each pass round the loop. The loop is the punch range. On a drum track each pass Layers into one clip, so you add a little every time round; on any other track each pass is a New take. Sketch's record strip switches it (Each pass), per track. A note you start a hair before the loop comes round (less than a 32nd early) is the next pass's downbeat, on the grid or in your own timing.
• Takes. A take covers the bars you played, from the bar you started in to where you stopped, and what played there before is muted under it, there and nowhere else. The passes and what was there before are one take folder: the clip says how many ("3 takes"), and that label lists them and plays the one you pick, with Previous take and Next take (⌘↑ ⌘↓ on the selected clip), Flatten to the one playing (the others go) and Delete. The takes are numbered in the order you played them. The last complete pass plays; one you stopped halfway through waits underneath with the others. A tune that runs on over the loop's end stays one take: its last notes go to the loop's start, where they came round. A last pass that's only a fragment of the others waits under the fuller one.
• Hum it in. With Sketch on Hum it, R records the mic as a hum, count-in and all. A hum already going when you press R becomes the take's. When the take is in, notes it moved into the song's key are counted, as when you hum on your own ("Moved 2 notes into A minor, the song's key."), and Undo there puts them back as you sang them, leaving the take in.
• Put it in the song. Played something without recording? It's in Sketch's Takes list, and Put it in the song (⇧R for the newest) places it at the beats where you played it if the song was running, else at the marker's bar.
• Tempo, meter and the loop wait until the take stops (they dim while it runs).
• The letter keys. While musical typing or Tap has them, the line under the song's title says so ("Keys play Bass", with the key that stops it), and the keys they play on are notes: K and L aren't the click and the loop then, nor S solo in musical typing. Click that line to hand the keys back.
• First time? Tap a beat on the Take one card, or on a new song's first screen, adds a Drums track if there is none, loops two bars with the click and starts them: press R and tap F J K L. While the song is shorter than 8 bars, Make it 8 bars (beside a kept take, and on the tour's last card) repeats it to 8: parts that don't fit evenly, like a 3-bar hum over a 2-bar beat, each come round on their own phrase.

Shape the song

• Where play starts. Click a bar on the ruler or in a lane, or select some bars, and the start marker goes there (its bar number printed in reverse on the ruler). Space plays from it and Space again stops and goes back to it, so you can work a part bar by bar. ⇧Space plays on from where it stopped, and Home puts the marker back at bar 1 (so does a click on the position). With the loop on, Space still plays from the marker and cycles once the playhead reaches the loop: a marker before the loop plays into it and round, one past its end plays on. R records from the marker too. Each song keeps its marker in this browser.
• Sections. Right-click a section's name in the ruler (long-press on a phone): Duplicate (⌘D) copies it and its clips right after it and moves what follows; Insert bars after adds 1, 2, 4 or 8 empty bars across the song; Delete these bars takes them out, with what's in them, and closes the gap.
• Clips. Right-click a clip (on a phone, hold it and let go): Repeat ×2 or ×4, or Split at playhead (⌘E). Notes cut by a split keep the part that sounds on each side, and every note keeps its author.
• Drop a clip on another (drag it, or ⌥-drag a copy) and it takes those beats, as in Live: what was under it on that track is cut away there and kept on either side, or goes if the dropped clip covers it whole. ⌘Z undoes the move and puts it all back in one go. A take folder under it is cut across all its takes, and the part after it is a folder of its own.
• A take folder moves whole. Drag any of its takes and all of them go along. On a comped folder (takes picked for different bars), a drag across the clip selects those bars; drag it by its label line (the name along the top) to move it.
• Mute or solo a track. M mutes the selected track and S solos it, from anywhere in the studio (with a clip selected, its track); the same key again unmutes or unsolos it. M and S on its header and its mixer strip do the same. On a phone, a tap anywhere on a track's header selects the track; M and S only take a tap on them.
• Stop one part. Mute (0, or the clip's menu) keeps a clip and silences it, even while the song plays: it is printed in outline, its name struck through and "muted" where its byline was, and it plays nowhere, not in the song, an export or a render. 0 again, or Unmute, brings it back.
• A take that runs on. Cut it down by dragging either edge, or with Trim to the loop: it keeps just the loop's bars, and what played under the part you cut off plays again. Mute and Trim work on every selected clip at once.
• Too much sound. All off, the red key at the right of the top bar (⇧Esc, from anywhere, even a text field), stops everything at once: every note, reverb and delay tail, preview and click, whoever started it.
• A mix that clips. The top bar's meter reads the mix before the master's safety clip. When the mix goes over 0 dBFS, the bars turn red and the number becomes Clipping 2.4 dB, the amount the clip is shaving off. Press it to pull the master down by that much, with half a decibel to spare: one undo step. The mixer's master strip says the same.
• Notes. The piano roll's Transform menu works on the selected notes, or the whole clip: humanize, quantize, strum, arpeggiate, transpose in the key, double an octave up, chords from a melody, continue a phrase, fill a gap and more, sixteen in all. Each is one undo step, and the agent has the same set.
• Notes as tab. Tab in the Notes toolbar shows a pitched clip as guitar tab. It holds the same notes, so an edit in either view is an edit in both, and a part written as tab (a kept riff, tab an agent wrote) opens that way. Click a fret number to pick its note (⇧ adds). Type a fret and the note moves there on its string, its pitch changing to match; ↑ and ↓ move it to the next string and keep the pitch. Higher string, Lower string, Fret −1 and Fret +1 do the same with a click. With Scale lock on, a fret outside the key is refused and the view says why. Tuning and Capo belong to the clip: changing them moves the fret numbers and leaves the pitches alone.
• Presets. An instrument with named sounds has a Preset line under its name in the Devices tab ("Preset Felt"). Pick one and every knob goes there, in one undo step; move a knob after and it says "Felt, edited". A device nobody has touched says Default, and a sound that is plainly one of the presets moved a little (a song built from it) names it the same way, "Sprocket, edited". The agent names the same sounds.
• Open a device big. Open on a device in the Devices tab (or a double-click on its name) opens it in its own window over the studio: every knob big, with its value, the presets (‹ › to step through them), A and B to compare two settings (each flip is one undo step), On for an effect, what it sends out as a scope, and for an instrument a keyboard along the bottom: click or drag along it to play, lower on a key for louder. The song, the transport and musical typing keep working while it's open, so you shape the sound as you play it. Drag the window by its top and size it from its corner; Esc or × closes it. When an agent turns a knob there, the knob flashes in its colour and the window says what moved. History names each knob in words, with where you left it ("Light Table: A pos 0.53"), and the studio's notes stand beside the window while it's open, or in its bar when there's no room, never over its knobs. On a phone it opens over the whole screen; on its side, its top is one row.
• Drums. Two kits are under Drums in Add a track, which lists every instrument by kind. Gobo Kit has a field kit, drum machines and a dusty sampler. Studio A is an acoustic kit in a big tracking room, miked like a record:
  • The mics. A close mic on every drum, a pair of overheads, a room pair and a crushed room, each a fader in the Devices tab: CLOSE, OH, ROOM, CRUSH, BLEED and SIZE.
  • The drums. KIT picks them: warm 70s maple, punchy birch, a small jazz kit, a big arena kit or a dead 70s kit. Every drum and cymbal has its own tune, decay and level.
  • How it plays. Harder strokes are brighter as well as louder, and no two strokes are alike.
  • What it plays. Besides the usual rows it plays rimshots, the ride's edge, the hats' edges and half-open hats, flams, drags, a roll for as long as you hold the note, and cymbal chokes. The Beat tab and the piano roll name every row by what the track's kit plays there, and More rows in the Beat tab adds any of them.
  • Its window. Open Studio A to see the kit drawn from above, each piece where it stands for the mics. Click a piece where you'd hit it: the middle, near the edge or the rim (a rimshot); the hats' tip or edge; the ride's bell, bow or edge. Lower on a piece is louder. Alt-click chokes a cymbal (on a touch screen, press and hold it), and drag up on the hats to open them (let go and the foot closes them). The pieces light as the song plays them. Click one to tune it, or to play every stroke it has from the keys beside the kit (hold Roll to roll). The mics are faders along the bottom, and VIEW turns the picture round with the stereo image. On a phone, tap the kit and scroll for the rest.
• A synth to dig into. Light Table is a wavetable synth. Each of its two oscillators sweeps through a table of waves (vowels, bells, organ drawbars, eight-bit pulses and more) as you turn its POS knob. A filter, three envelopes, four LFOs and eight mod slots move almost any knob for you. Start from a preset: its description begins with what it's for (Bass, Lead, Pad, Pluck, Keys, Arp or FX). The four MACRO knobs do nothing until a mod slot uses one.
• Shape the tone. Slide Rule is an EQ: put it on a track like any effect and open it, and you get its curve over the live spectrum of what comes in and what goes out. Double-click the line to place a band there, then drag the band's square for its frequency and gain (⇧ for fine steps, ⌥ or the scroll wheel for how wide it is; on a phone, double-tap to place one and spread two fingers to widen it). Double-click a band to put it back to 0 dB. Right-click it (or hold it on a phone) for its shape (bell, shelves, cuts at 12, 24 or 48 dB per octave, notch, band pass), to switch it off, or for Solo: you hear only the part of the sound that band works on, so you can hear what you're cutting. Tab moves between bands and the arrow keys move them. Auto gain holds the level where it was, so you judge the tone and not the volume. Its presets are starting points ("Clean up the low end", "Vocal presence", "Air", "Telephone", "Kick: thump and click"), and each band's square is outlined in the colour of whoever set it last.
• Pump, gate and pan in time. Put Scribble Strip on a track (Add an effect, in the Devices tab) and Open it. Draw a shape and it moves the volume, a filter or the pan in time with the song: Volume, Filter and Pan are tabs, each its own shape, depth and rate (1/32 to 2 bars). Click to add a point, drag one to move it (⇧ for off the grid), drag the small square on a line to bend it, right-click a point to make it a step or delete it; Pencil paints steps on the grid, and Snap sets the grid. The presets under it are drawn: Pump (quarter notes), Gate (sixteenths), Stutter, Swell over a bar, Auto-pan, Filter wobble and more. Smooth softens the edges so a hard step doesn't click (all the way down, it does). While the song plays, a green dot rides the line and says what it's doing there (−6.0 dB). With a point picked, the arrow keys move it, Enter makes it a step and Delete takes it out.
• Light Table's window. Open it big and each oscillator's table is drawn as a stack of its waves, the one it plays lit: drag up or down on the drawing (or turn POS) to move through them, and 3D, Wave and Harmonics change how it's drawn. Click the table's name to pick another; each is drawn small with a few words on how it sounds.
• Drag to modulate. Every source has a jack, the small socket beside an envelope's or an LFO's name, under each macro, and beside Velocity, Note, Wheel and Random. Drag one onto a knob and the first free mod slot takes it: the knob gets a ring, and the ring's arc is how far the source moves it. Drag the ring up or down to change that, and right-click it to take it off. Each of these is one undo step. A click on a jack and then on a knob does the same (on a phone too, across tabs), and the Mod matrix tab lists all eight slots as sentences ("LFO 1 → A POS, +35%"). When all eight are in use, it says so. While the song plays, the table, the filter's curve and the rings show where things have moved to.
• Make it loud and finished. Put Gaffer Tape on a synth, a drum bus or a vocal and Open it. It hears the sound in three bands, low, mid and high, and in each it lifts the quiet detail up and holds the loud parts down. Depth is the big knob: how much of it you hear. It starts at 40%, about as loud as it came in; turn it up and it gets denser and louder. Full depth, Drum smash and Vocal presence make a part louder, by 1 to 3 LU on drums; Subtle 30%, Glue (bus) and Bass tighten keep it about level. Under Depth, while the song plays, the window says what it is doing to the level: the loudness coming out against what went in, in LU ("+2.1 LU, louder than it came in"; a part it takes a decibel or more off reads in yellow, and the window's top line says so too), with an In and an Out meter. Nothing it puts out goes over −1 dBTP. Each band draws its curve, level in to level out: drag the hollow square sideways to set where it starts holding down and the filled one for where it starts lifting (⇧ for fine steps, a double-click puts one back). Drag the two lines on the strip above to move where the bands split. While the song plays, each band says how far it is holding down or lifting the sound, with a bar, and a green dot rides its curve where the band is now. Time makes every band react faster or slower; a fast Attack (under 5 ms) catches each hit's front, a slow one lets it through. Thresholds and splits take the arrow keys too.

Grooves

The Grooves tab, beside Beat, is a drummer's book. The styles run down the side, from rock and funk to bossa, trap and gospel. Each has grooves for the parts of a song: intro, verse, chorus, bridge, a half-time feel where it fits, fills of a beat, two beats and a bar, and an ending. Each groove is drawn as a picture of its hits: the bigger the mark, the harder the hit, and a hollow mark is a ghost note. They play with a feel, not on a grid: swing that tightens as the tempo rises, a neo-soul snare a little behind the beat, punk hats a hair ahead, and a drummer's small drift.

• Hear plays the groove you picked at the song's tempo, from the bar in the Put it at bar box: alone, or with the song in place of its drums. Stop, Space or Esc ends it. Nothing goes into the song.
• Put it at bar puts it on the selected drum track (or a new Drums track) for the bars you give. Whatever was under it on that track is cut away, as a clip dropped in the arranger cuts, and one undo brings it back. You can also drag a groove onto the arranger: it lands at the bar you drop it on.
• Tap to find. Tap two bars or so on the Kick, Snare and Hat pads; after the first tap, F J K play them. When you stop, the five closest grooves come back with the tempo you tapped. They play at the song's tempo.
• Build drums for the song writes a whole drum track in the style of the groove you picked, one you found by tapping too. Each section gets its part's groove (by its name, Verse, Chorus, Bridge, or by how busy the song is there), a fill where sections change, a crash on each new one, and the style's ending. When the loop runs to the song's end, the ending is left out so the loop goes round. First it says what it will do ("Pop, verse groove in bars 1–4 and chorus groove in 5–8; fills at 4 …"). Tap a section's part to change it, pick End with the style's ending or Loop it, no ending, then Build it. It goes on a new track, as one undo step. Drums already in the song keep playing beside it: M on a track's header mutes one.

On a phone the tab is one column that scrolls, upright or on its side. Agents get the same with find_grooves, use_groove and drum_track. Ask the demo agent for "a funk beat" and it offers three from the library as takes.

Automation

Any knob, fader or pan can move over the song. Its moves live in a lane under its track, and lanes play whether they're shown or not.

• See the lanes. E shows or hides the selected track's lanes (a track with none opens on Level). Automation… in the track's menu lists them and has Add a lane… for Level, Pan or any knob; right-click a knob (hold it on a phone) and Automate opens its lane.
• Draw. Click a lane to add a point; drag a point to move it (⇧ for fine, off the grid), drag the line between two points to move both, ⌥-drag the line to bend it, double-click a point to delete it. Draw on the lane's header (or hold ⌘ while you drag) paints freehand. Drag across an empty stretch to select its points; the arrow keys step from point to point and raise or lower them, and Delete takes them out. Every gesture is one undo step.
• Shapes. Select some bars and right-click the lane: Ramp up, Ramp down, Swell, Dip, Hold here or Pulse over them, or Simplify, Clear and Hide this lane. Right-click a point for Straight, Ease in, Ease out or Step. A ramp goes where the lane is going and holds there: to the value after the bars, or the one it jumps to at the next section; on a level stretch, half the knob's travel, held until the lane next moves. The toast says the numbers, and when the lane already does it, it says that instead.
• Record a move. Press R and turn a knob or pull a fader while it records: what your hand does is written into that control's lane, from where you touched it to where you let go, and then the lane takes over again with a 200 ms glide. Only the stretch you touched changes. The moves go in with the take, as one undo step (⌘Z takes both back out); round a loop, the last pass you moved it in is the one that plays.
• A move while the song plays. Turn a knob while the song just plays and the toast says what moved, and that it stays where you left it ("Cutoff moved from 400 Hz to 6.2 kHz over bars 9–11. It stays where you left it."). Write it into the lane writes the move into the lane as if you had recorded it. Leave it and the knob simply stays where you put it.
• A knob with a lane turns by itself and says auto. Turn it yourself and the lane steps aside: the knob says held, and Back to the lane (in the toast, the knob's menu or the lane's header) gives the lane back. With any held, Back to the lanes in the top bar gives them all back at once.

Jam

Jam, the tab beside Arrange, is a room for playing guitar over a song: to find ideas, try tones and learn the changes. The song keeps playing when you switch, and what you record there is in the arranger when you come back. The room takes the screen: the detail pane steps aside while it's open (D brings it back, and then it stays) and returns when you leave. From the top: the chord, then two tabs, Neck (the tab and the neck) and Rig (your amp and pedalboard), then your guitar and practice, then ideas. The song plays on whichever tab is open.

• Play over something. The song on screen is the band. Its name at the top opens the others: Jam tracks (a blues shuffle in A, a funk vamp in E minor, indie in G, a ballad, neo-soul, a metal chug, reggae, bossa nova, lo-fi and classic rock), the demos and your recent songs. Make your own takes a style, a key, a tempo and your own chords ("Am F C G", or numerals like "I IV V"). A jam track opens like a song: the one you had goes to Recent songs, and Undo brings it back. Another song starts at full speed, with nothing left on the neck from the last one, and with your guitar still plugged in it gets an audio guitar track at once, so you keep hearing yourself.
• Follow the changes. The chord now is big, with its notes; the next one counts down in beats; the section and the bar sit beside them. A long name ("Dbmaj7/Ab") gets smaller rather than cut off. The chords are read from the song's notes, so take them as a good reading, not gospel; a song made only of audio clips has none.
• The neck. The pentatonic box, the key's scale, the chord's tones (by interval, or by name with Note names) and the next chord, fading in as the change comes; each one toggles. Pick a tuning (standard, drop D, half-step down, DADGAD, open G), or Left-handed. What you play lights up wherever it falls: filled when it fits, a ring when it's outside, and the line under the neck says what it is ("G: the blue third over E7; bend it a little toward G#").
• Your guitar. With an interface, choose it and its input under Your guitar and open it. An interface or a line input you pick is monitored at once, through the Guitar track's effects, and the line under it says through which tone; a microphone stays unmonitored, since through speakers it howls, and the line says that too. Monitor turns it on or off by hand. Your guitar's track starts loud, where a guitar at an interface's usual level sits over the band. Match the band listens while you play along for five seconds and puts your guitar 3 dB over the band, one undo step; it never goes past the fader's top or pushes the master into clipping, and it says where it landed. The tuner names a note and how far off it is once the note settles, and only a guitar's notes.
• No guitar? Musical typing, a MIDI keyboard or a tap on the neck plays a guitar sound: turning musical typing on in the room gives the keys a guitar track when the song has none. A line by the neck says when the keys play something else.
• Rig. Your tone, laid out the way it sits on a stage: the amp big, the pedalboard under it. The chord stays at the end of the tabs' row while the rig has the room.
  • The rig's name sits at the top, with what it's for and where it is in its bank. The arrows beside it (or [ and ]) flip through the Guitar Studio's rigs: you hear each one at once, and the one you rest on is one undo step. The words under it pick a bank. A rig whose pedals you've changed says edited.
  • The amp is drawn at full size: turn its knobs by dragging up and down, the scroll wheel or the arrow keys; its power switch takes it out of the chain. Cab & mics under it names the cabinet and the mic, and Adjust opens their controls.
  • The pedalboard runs in signal order, left to right: your guitar's jack, the pedals, the amp's place in the chain, then any pedals after the amp, out to the mixer. Stomp a pedal's footswitch to bypass it. Drag a pedal by the tape under it to move it (or focus the tape and use the arrow keys); its × takes it off. Add a pedal, before the amp, opens the effect list. Each of these is one undo step. The board scrolls sideways when it's wider than the room.
  • A tone, a knob or a change on the board goes on both guitar tracks, the keys' and your interface's, so what you play on either, and what Show me plays, sound alike.
• Practice. Loop loops the section you're in (⇧L; again to stop). The speed slider plays it at 50–100% (- and =) without changing the song; audio clips sit out below 100%. Recording your guitar through the interface plays at full speed, and your speed comes back when the take stops; leaving the room or opening another song puts it back to 100%. Band turns everything except your guitar down, to 24 dB, so you can hear yourself over a loud song. It's for practice only: the song's faders, its renders and its exports stay as they are. While it's down, the top of the room says Band −6 dB (or however far); press that, or double-click the slider, to put it back. Leaving the room or opening another song puts it back to 0 dB. Match the band turns the band down for you when the top of your guitar's fader isn't enough to sit 3 dB over it, and says by how much. Click and Count-in are the transport's.
• Ideas. Tips from this song's chords: the scale and where it sits on the neck, the note to land on at the next change, the notes outside the key, a section that moves key, and a two-bar lick. Show puts one on the neck and brings the neck into view. Show me plays the lick: while the song plays it waits for its own bars and plays in time with the band (when the loop never reaches them, it starts at the next bar line and the neck says why). Hearing a lick or a chord changes nothing in the song: it plays on the room's own guitar, not a track. The tips hold still while your pointer is over them. The chips under them ask the agent.
• Keep it. R records what you play onto the Guitar track from the playhead (again: punch out). In the room it never starts a hum.
• On a phone. The sheet tucks away when the room opens, and comes back when you leave. The chord sits on one line with the neck straight under it and a Record button by the neck. A swipe that starts on the neck scrolls the room; a tap plays the note. Show and Show me bring the neck back into view. On Rig the amp sits above the pedalboard, and the board scrolls sideways under your thumb; to turn a knob, hold it still for a moment, then drag.

Tab

Under the chords, the room shows the Guitar track's part as tab: six strings, the fret each note starts on, its length drawn along the string, the bars numbered and the chords above them. While the song plays, the note sounding now is printed in reverse and lit on the neck. The notes ahead are in plain ink and the ones behind in pencil. Copy tab copies it as text. With no riff and no part to show, the tab is one line with Suggest a riff in it.

• Suggest a riff. It writes three riffs for the section the playhead is in, in the song's key and style (or the style you pick) at the difficulty you pick. Each is a one- to four-bar idea that repeats and changes a little, with chord tones on the strong beats, played in one hand position. They come from the house riff writer, a seeded program in the studio, and the lane says so. With an agent connected, the button asks the agent instead; or the house writer's still gets the studio's. Hold to hear plays a take through your tone while you hold it. Keep puts it on the Guitar track as one undo step, and Another writes three more.
• Learn a riff. Loop bars 5–8 loops the riff's bars. Play from bar 5 plays them after a bar of count-in, and Speed slows them down (− and +). Turn off Hear the riff and it goes silent, so you play it. Learn it waits on each note until you play it, then moves on, and the line says what to play ("Waiting on the A: open, A string").
• How it went. Play along on your guitar through the interface, with musical typing, a MIDI keyboard or taps on the neck. A note you hit turns warm. A note you play early or late gets a ring, with a tick on the side you were. A note you miss stays plain. After each pass a line says how it went ("11 of 14, the bend in bar 2 is late"). Chords are judged on when you strike them and on their lowest note only, because the pitch tracker hears one note at a time; the lane says so under a part with chords.

An agent can read the room, make a jam track, set a tone, point at the neck, and read and write tab (the tools).

On a phone

The detail pane is a sheet under the song: drag its handle to size it, or tap the handle to tuck the sheet down to its tabs. Turn the phone on its side and the top bar takes one row, and the top of the song stays in view however far the sheet comes up. A swipe scrolls. Sketch's Play it is an octave of keys in the song's key, with the line over them that musical typing has (Snapping to 1/16, in C minor): tap either part to turn it off. To move a knob, a slider or a fader (a pedal's, a device window's, the mixer's), hold it still for a moment, then drag: a swipe that starts on one scrolls past it and moves nothing (one that scrolls nothing says how); in the Beat grid a tap adds a hit, and a hold, then a drag, paints along the row. In the browser a tap on an instrument asks where it goes, a new track or in place of what the selected track plays, so a look never swaps a sound out. Two notes show at a time, and the same one again is counted (×2), not stacked. In Jam the chord sits on one line above the neck, the neck scrolls sideways, and a tap on it plays that note; the tab scrolls sideways with the playhead.

Bring your own Claude

The demo agent is a script. For the real thing, open the Agent tab, paste an Anthropic API key and pick a model: Opus 5.5 (the default), Sonnet 5.5 or Haiku 4.5.

The key stays in that browser and goes only to api.anthropic.com. The page calls the API directly, with no Overdub server in the middle, and you pay Anthropic for what you use.

Ask it the way you'd ask a session player: "darker", "half-time in the bridge", "two takes on the hats". It acts on what you've selected, says what it changed and the number, and asks which one you mean when a word like "warm" could go two ways. Anything that rewrites your notes comes as takes for you to pick from.

When it asks, you hear both readings and pick one. Your picks are kept under Your words in the Agent tab's settings (the gear), in that browser, so next time "warm" means what you picked and the agent says it used it.

Bring Claude Code

Claude Code (or any agent that speaks MCP) can drive the studio too, with the same tools as the agent in the page. It needs a copy of the studio running on your own computer: the public site can't be driven from outside. Clone https://github.com/aj-dev-smith/overdub, or install the plugin, which fetches it for you.

The plugin brings the server and a skill that teaches Claude the room's rules. Inside Claude Code:

/plugin marketplace add aj-dev-smith/overdub
/plugin install overdub@overdub

Or, from a clone, add the server alone:

claude mcp add overdub -- node <repo>/server/mcp.js

Then ask: "Look at my Overdub song and give me two takes on the bassline." The first tool call starts the local server if it isn't running and opens the studio at http://localhost:3279/app/. Keep that tab open. Claude Code shows up in the Agent tab as a presence, and its edits are signed mcp:claude-code.

Or skip the terminal: with the studio running from your clone (node server/serve.js) and Claude Code installed and signed in, the Agent tab offers Use Claude Code here. Then the Agent tab's own box talks to Claude Code on your computer, on your Claude plan rather than an API key, with the model you pick in the Agent tab's settings. It sees only the studio's tools, and its edits are signed claude, like the agent in the page. Each song keeps its own conversation; New starts it over.

Songs are kept per site, so a song on the public studio and one on localhost are separate. Move one across with the Song menu: Save the project file (⌘S) on one, open it (⌘O) on the other. More, for Claude Desktop, Cursor, VS Code and Codex too: Connect an agent.

Build a device

Ask for an instrument or an effect that doesn't exist yet: "Build me a pedal that makes my guitar sound like it's underwater in a cathedral." The agent writes it as a small piece of audio code.

• The check. Before you hear it, the studio checks it: it has to compile, never output NaN, stay under control at the ends of its knobs and never leave a note stuck. Its loudness is measured against what went in. A device that fails doesn't play, and the agent gets the report so it can fix it.
• The face. A device that passes gets a face drawn from its knobs, with a badge saying who built it. Every knob drags, takes the arrow keys and resets on a double-click.
• Export and import. In the Devices tab, a device's i card has Export device: a .overdub-device.json file. In another song, Import a device… in the Song menu (⌘⇧I) brings it in. It is checked again on the way in, and refused, with the report, if it fails.

The device library has 44 devices: the 31 built-in instruments and effects, and 13 Claude wrote, each from one request, and the request is on the card. Play any of them on the page. The Guitar Studio's 101 pedals and 27 amps aren't on that shelf; find them in the studio's browser. To write one by hand, see Writing devices.

Share and fork

Share a link in the Song menu copies a link with the whole song in it: notes, devices (including ones written in the song) and the mix. Audio recordings stay behind, and the studio says so. The song is packed into the link itself, so Overdub's servers never see it, though whatever you paste the link into (a chat, an email) does. The first time, it asks whose name the link should carry (your parts are signed with it) before it copies anything; this browser keeps the name, so after that it copies straight away. Change the name in the sheet and Copy link copies the link signed with the new one.

A link can carry devices someone wrote, and a device is code that runs in your browser when the song plays. So the studio asks first. Under the banner it says what the song brings, who wrote it, what you're hearing without it and what playing it means: "This song brings 2 devices Sam wrote: Tin Whistle and Half Measure. They're off now: Tin Whistle is silent and Half Measure lets the sound through untouched. Each is a small program that runs on this computer. Play them if you trust Sam: that code then runs from now on, in this browser, in any song." Until you answer they're kept off, so if you press play first you hear the rest of the song, and the silent track's clips say kept off on the lanes.

• Play them, if you trust whoever sent it, lets them play now, no reload, and this browser trusts that code from then on, in any song: the same link won't ask again.
• Keep them off leaves them off. The song plays without them, the track says kept off, and the next time the song opens it asks again. Play it on a kept-off device in the Devices tab lets that one play later: the tab opens on the first track with one, and its track list says kept off beside each of them.

On a phone the question comes first, on its own; once you've answered, the banner is one line (▶, the title, Make it yours, Back), so the song stays in view. The banner's ▶ plays the song and stops it, from the start marker.

A song file you open (⌘O, or dropped on the studio) asks the same way. Nothing asks about the demo songs, the devices your agents write here, or a device file you import: those are yours to run. Make it yours keeps whatever you decided.

Whoever opens the link hears your song but doesn't keep it yet: nothing is saved in their browser until they press Make it yours. Their copy remembers where it came from, and every part stays signed by whoever played it: Claude's takes stay Claude's, and yours come over signed by a guest, so nobody mistakes them for the new owner's. A device stays credited to whoever made it, and one that reached the sender in someone else's link says so ("Sam, via Jo's link"), so a song that comes back to you still credits what you made. The welcome card a first-time listener sees names who sent the song. History and the provenance report both name the song it was forked from.

When you open someone else's link, your agents can play over their song, but until you press Make it yours they don't take anything out of it on their own. An agent that wants to delete something, rewrite notes or automation that's there, or add a device it wrote asks first, with a card in the Agent tab: "Claude wants to delete Bass (Sam's part)." Keep does it, signed by the agent; Keep as it was leaves the song alone; Hold to hear plays it as it would be. A new device is code, so it runs only once you keep it, after the device check. Adding a part, a clip or an effect, or a mix move, goes straight through as usual, and after Make it yours your agents work directly again.

Bring material in

• MIDI. Drop a .mid file anywhere in the studio, or use Import MIDI… in the Song menu. Each part becomes a track with one clip (drums on the drum kit, other parts on the nearest built-in instrument), all in one undo step. Into an empty song it also brings the file's tempo, meter, key and markers; into a song with clips, the song keeps its tempo and says so.
• Audio. Drop a WAV, MP3, M4A or OGG file on the arranger: it lands where you dropped it, on that audio track or a new one. Import audio… in the Song menu puts it at the playhead's bar.
• A reference. Open the Reference tab (bottom panel, after the Mixer) and drop a finished song you want yours to sit near. It is measured once and kept beside your song, never in the mix or a render. Measure the mix shows your mix's numbers beside it, and A and B switch between your mix and the reference, played at your mix's loudness. Ask the agent how yours compares and it measures both (compare_to_reference).

Take it elsewhere

The Song menu's Export section:

Save the project file (⌘S) keeps the song itself as .overdub.json, every note and device. Open it again with ⌘O.

Keys

? shows every key in the studio, grouped, and has a switch for single-key shortcuts: off, keys like R and H do nothing, so dictation or a stray key can't start a take or open the mic. The ones to learn first:

On Windows and Linux, Ctrl stands in for ⌘. The keys are the ones Logic and GarageBand use: M mutes, S solos, K is the click. Splitting is ⌘E, Ableton Live's key, since a browser keeps Logic's ⌘T for a new tab. (Until October 2026 M was the click and S split a clip; the first press of each moved key says so, once.) A key from another DAW that does something else here (⌘L, ⌘C or ⌘V on a clip) says what does it: L loops the selected bars, ⌥-drag or ⌘D copies a clip.