MOSASAUR LABSGet Mosasaur Mono 1.30.101 ↗

MOSASAUR / FREE MONOPHONIC SYNTHESIZER

Two layers.
One evolving
voice.

A free monophonic synthesizer with two independent layers and 1,078 factory sounds. Draw a waveform, shape a vocal tone, follow a moving texture—or capture your own sound and play it again.

Download Mosasaur Mono 1.30.101 ↗Buy Me a Coffee Explore the sounds ↓

APPLE SILICON · macOS 13+ · AU / VST3 / STANDALONE · 1.30.101

The complete free Mono edition includes both sound-design layers. It plays one note per layer; unison adds copies. Polyphonic modes belong to the separate Mosasaur Poly product.

01 / THE INSTRUMENTDUAL-LAYER · MONOPHONIC
A sound you can keep digging into.↗

02Independent
sound layers

08Shared performance
macros

1,078Factory presets
plus Init

One played note.
A world of movement.

1,078STARTING POINTS.
NO FINISH LINE.

THE PRESET SHOWCASE

Find a bank.
Follow a sound.

56 sounds selected by Mosasaur’s creator from 17 banks and categories. Explore each collection, from quiet resonances to the psychedelic movement of Hole in the Sky.

Every sound here is included with Mosasaur. Download once for all 1,078 factory presets plus Init.

56 samples across 17 groups

Alien Worlds

2 selected sounds
PRESET 12

Cryogenic Dawn

A smooth slow bloom from a dim fundamental into a pale upper shimmer.

PRESET 13

Beacon Beyond Pluto

A rounded lonely ping followed by widely spaced dark echoes.

Dangerous Toys

3 selected sounds
PRESET 08

Rubber Monster

A huge elastic monster growl: a snapping resonant mouth, bent pitch and a heavy rubbery bottom.

PRESET 10

Porcelain Smile

A shattered ceramic impact blooms into an ominous detuned metal cloud.

PRESET 14

Do Not Pull String

A rough talking lead whose moving harmonic peaks shift between open and pinched vowels.

Delay · Echo Worlds

3 selected sounds
PRESET 05

Dub Furnace

A gritty Tape echo with a decaying tail; sweep Echo reach for repitch dives.

PRESET 07

Backward Lantern

Half-note reverse Tape blooms feed a gentle MosaTap cloud.

PRESET 27

Wire Nest

Noise-only fuzz contour woven through a tuned oscillator spine.

Distortion · Tempered Violence

3 selected sounds
PRESET 05

Acid Concrete

A resonant acid bite driven into a coarse overdrive stage; slides between notes while its mouth opens.

PRESET 12

Slag Hammer

A low explosive strike followed by a short rasping metal tail.

PRESET 28

Phase Wound

A deeply phased fuzz bass: strong sweeping cancellations move through a driven, sustained core.

Dynamics · Living Pressure

3 selected sounds
PRESET 09

Tidal Glass

Soft Opto levelling and Grain on Osc 2 make a slow glassy cloud.

PRESET 12

Broken Halo

Splice and coloured FET compression make a restless, torn halo.

PRESET 20

Last Light Engine

Master Glue links a wide lead and triplet MosaTap, with a firm output ceiling.

Echo Atlas

3 selected sounds
PRESET 02

Prismatic Bell Ladder

Glass bells bounce left and right on unequal times, with gently changing brightness.

PRESET 03

Dub Chord Relic

A minor chord stab feeds centered tape echoes that darken and compress on each pass.

PRESET 11

Rubber Room

A resonant rubbery bass pluck trails pitch-wobbled echoes with shifting crossfeed width.

Fracture · Grain Explorations

6 selected sounds
PRESET 03

Reverse Excavator

Down-octave reversed scraps drag behind a dry sub anchor.

PRESET 17

Glass Needle

Bright near-sine FM-style plucks split into tiny pitched grains.

PRESET 23

Velvet Undertow

A slow dark wash of smooth overlapping grains, with a restrained dry center.

PRESET 30

Reverse Bloom

Nearly all-reversed long grains bloom out of the last played note.

PRESET 32

Stillwater Shards

A clear pad with sparse bright fragments and a slow, deep history scan.

PRESET 36

Radio Shards

A narrow metallic signal breaks into irregular grain transmissions.

Haunted Depths

3 selected sounds
PRESET 01

Crypt Pressure

Deep double-saw pressure with a faint minor-second beat and slow filter breathing.

PRESET 07

Seance Wires

Inharmonic wire-like tones and wavering pitch above a solid sine-sub foundation.

PRESET 15

Leviathan Requiem

A massive layered finale: detuned low saws, a tritone halo and a crawling semitone voice.

Hole in the Sky

5 selected sounds
PRESET 01

Velvet Black Hole

An octave-wide falling fuzz ribbon pulled through a resonant flanger; its stereo tape echoes rise while the source falls.

PRESET 07

Mercury Staircase

A continuous ascending octave spiral with falling replies and a wide stereo orbit.

PRESET 19

Bell Through Violet Glass

A metallic strike scatters into reverse grains with random pitch, followed by separately bending stereo echoes.

PRESET 23

Moth Inside a Jewel

A bright point becomes a cloud of short, high, mostly reversed grains; fast pitch tremor rides on a slower six-semitone descent.

PRESET 25

Seven Doors Turning

A sixteen-step interval ritual turns against a faster amplitude pattern; the filter cycle continually speeds up and slows down.

Hostile Geometry

4 selected sounds
PRESET 11

Anvil Bloom

Heavy struck metallic hit; a dense attack decays into a hollow harmonic tail.

PRESET 16

Ratchet Reactor

Rapid irregular stepped morph sequence with chopped dynamics.

PRESET 17

Concrete Clock

Low mechanical pulse with alternating harmonic gaps and dry centre.

PRESET 28

Implosion Signal

Descending impact-like burst with a long resonant tail.

Living Current

2 selected sounds
PRESET 02

Copper Escalator

Wide octave-and-fifth steps rise and descend through tape warmth.

PRESET 04

Prism Terraces

Glassier phase-modulated minor steps reach upward and tumble down.

MosaTap · Time Machines

4 selected sounds
PRESET 01

Clockwork Alloy

Six alternating taps answer a clipped sixteen-step pattern.

PRESET 07

Cathedral Ash

Dark wide harmonies slowly dissolve into a sixty-four-tap cloud.

PRESET 12

Frozen Choir Vessel

Play a few notes to fill the cloud, then raise macro 8 to hold it.

PRESET 18

Chrome Needle Arp

A glassy arpeggio rides alternating rising and falling tap bursts.

Nuclear Textures

4 selected sounds
PRESET 06

Shattered Halo

Hard Clip NUKE. A dissonant high halo with hard clipped ridges and spacious tails.

PRESET 08

Bent Pendulum

Asymmetric NUKE. A lopsided resonant swing that rolls across the stereo field.

PRESET 17

Velvet Sawblade

Fuzz NUKE. A blunt buzzing blade swells rhythmically through a resonant filter.

PRESET 18

Ash Choir

Fuzz NUKE. A smoky sustained fifth opens gradually into dense, soft-edged fuzz.

Permanent Waves

4 selected sounds
PRESET 06

Neon Needle

Narrow bright lead with a focused upper-harmonic whistle.

PRESET 15

Wire Garden

Bright string-like pluck with slow stereo beating.

PRESET 18

Sunken Choir

Dark vowel-like pad with a fifth above a stable root.

PRESET 26

Fault Glass

Sparse angular harmonics with mild phase modulation and torn edges.

Resonant Vessels

2 selected sounds
PRESET 01

Deep Bronze

Deep bronze bowl tones with a long, exposed ring.

PRESET 11

Clear Quartz Bloom

A luminous, softly struck bowl with slow shimmering mode pairs and a smooth, exposed fundamental.

Rupture · Splice and Nuke

4 selected sounds
PRESET 04

Blacktop Crusher

Low, wide tearing bass with slow grain movement and a distorted Sub foundation.

PRESET 09

Siren Autopsy

Biting pulse lead; feedback PM and a rising sequence pull against unstable grains.

PRESET 15

Scrap Cathedral

Metallic ring-and-PM sequence through wavefold, phaser and a restrained dark reverb.

PRESET 18

Rust Storm

Noise-laced gated fuzz with irregular grains, slow ring movement and dark space.

Bass

1 selected sounds
BASS PRESET

Phased Sweeping Bass Distorted

A distorted bass with a sweeping phaser character.

Rendered directly from Mosasaur factory presets. Playback levels are balanced for this showcase; no added effects. Choose any player to listen. Starting a new sample pauses the previous one.

All 56 selections are included in the factory library.Download Mosasaur Mono 1.30.101 ↗

01 / UNDO, REIMAGINED

Revisit an edit.
Keep what came after.

That earlier Resonance change no longer fits? Mute it in History, then keep the envelope, pan and other edits you made afterward. Restore it to compare ideas.

Selective muting applies to eligible edits in the current patch history. When edits affect the same control, the latest active value wins.

Try selective History · Quick Start, page 5 ↗
Muting and restoring an earlier Resonance edit while later edits remain active. Muted UI demonstration; use the player controls to pause.

02 / SEE WHAT YOU HEAR

See your sound
take shape.

Watch a saw change as Body and NASTY reshape it. Explore Scope, Spectrum, Spectrogram, Modulation and Stereo views at the source, layer or master.

The Mixer brings source, layer and master levels together. Master True Peak and loudness meters help you judge the final output.

Spectrum ↗Spectrogram ↗Modulation ↗Stereo ↗Mixer ↗
Try the Scope comparison · page 19 ↗
Look inside the Mixer
Mosasaur Mono Mixer
Inspect source, layer and master levels. True Peak and LUFS metering are provided on the master.
Actual source Scope as Body and NASTY change a held Init saw. Muted UI demonstration; use the player controls to pause.
Spectrum Analyzer previewSpectrum ↗Spectrogram Analyzer previewSpectrogram ↗Modulation Analyzer previewModulation ↗Stereo Analyzer previewStereo ↗

03 / A VOICE WITH NO SINGER

Shape a vowel.
Give it a phrase.

Choose Voice from an oscillator’s Wave menu. Move between vowels, change the vocal character and enter a short phrase in Lyric mode. These are synthesized vocal tones; no recorded singer or sample library is required.

Glottal is also available for a simpler vocal excitation source.

Make your first vocal sound · page 11 ↗
Mosasaur Mono Voice
Synthesized vocal tones, vowel shaping and lyric playback, without a sample library.

GO DEEP. STAY IN CONTROL.

A little warmth.
Or a completely different beast.

Shape the harmonics, sculpt the movement,
and put the changes under your fingertips.

01 / TONE & TEXTURE

Give every oscillator
its own personality.

Ten distortion types, from Warm to Wavefold, Fuzz and Bit Crush. Character shapes the oscillator before distortion. Push WRECK through 1x, 5x and 10x to NUKE, with extreme Wavefold, Tear and Gated Fuzz shaping.

RoundedHollowBrightMetallic
02 / ENVELOPES

From a sharp strike
to a slow unfolding.

Separate amp, filter, source and modulation envelopes. Shape the attack and stretch amp, filter and modulation timing with independent 1x / 5x / 10x controls.

Attack smoothingUp to 40-second stages*
03 / MODULATION

Make movement
part of the sound.

Sixteen modulation routes per layer. Connect LFOs, envelopes and performance sources to the controls that matter. Use eight shared macros to bring changes together.

04 / CONNECTIONS

Go beyond
the waveform.

Phase modulation, ring modulation and hard sync open up new textures. Refine them with source and layer EQ, unison, stereo placement and effects.

05 / SOURCES

Draw it, scan it,
sample it, or sing it.

Custom: draw two frames, edit their harmonics and morph between them. Wavetable: import or edit tables and scan their frames. Sample: import WAV/AIFF, set root pitch, trim, loop and retrigger. Voice: synthesize vowels and phrases.

*At 10x on supported amp, filter and modulation time stages. Source envelopes have their own ranges. Character availability depends on waveform.

TEXTURES WORTH GETTING LOST IN

Three ways to
change the conversation.

Try the quick-start recipes ↓
01 / INSIDE THE OSCILLATOR

Splice

Moving phase jumps and crossfades turn a familiar waveform into a jagged, restless texture. Find it in the oscillator Character menu.

02 / CAPTURE AND REARRANGE

Grain

Capture up to four seconds of played audio. Scatter, pitch and reverse its fragments, then freeze a moment into a shifting cloud.

03 / ECHOES WITH PERSONALITY

MosaTap

Up to 64 taps with stereo movement, Smear, Drift and rhythmic Chop. Watch the live map as the pattern unfolds.

Start with eight macros. Move with the XY pad.

Bring several controls together without hunting through the instrument. Add a Motion arpeggio or sequence, then shape its pitch, velocity, ties, probability, ratchets and step conditions. Run freely or follow your host’s tempo.

04 / CAPTURE AND RESAMPLE

Mosasaur can
play itself.

Capture a sound you made, put it into a Sample source, and play it at another pitch. Use an offline capture for a held sound or Live Capture for a performance and moving controls.

Import your own WAV or AIFF files and build a personal library with collections and favorites. Managed copies leave the original files in place; saved presets can include their sample audio.

Capture your first sound · page 14 ↗
Mosasaur Mono Sample playback
A real Mosasaur tone captured into Sample, ready to trim, loop and play at different pitches.

PICK A SOUND. START MAKING IT.

A few minutes.
A new starting point.

Six practical recipes from the illustrated Quick Start.
Listen, then follow the exact settings in the PDF.

THE CURRENT INSTRUMENT, UP CLOSE

Follow your curiosity.

Explore current Mono screens.
Choose a view and enlarge it to inspect the controls.

01 / 18

Sound

Start at the source: oscillators, Sub and Noise, filter, Character and envelopes.

Actual Mosasaur screens. Select a view, then enlarge it to inspect the controls. Example settings and preset counts vary.

A NEW VIEW. MORE SOUNDS TO EXPLORE.

Choose your light.
Follow the echoes.

Current Mosasaur Mono Sound page in the Light theme
The current Mono interface in Light. The same controls are available in Dark.

Dark or Light. Your choice.

Switch the synth’s appearance to suit your studio. Choose pale panels and dark labels, or stay with the familiar Dark theme.

Evolving textures, drones and echoes.

Living Current brings evolving textures and flowing sequences. Haunted Depths explores heavy, discordant drones. Echo Atlas puts pronounced, changing echoes at the center of each sound.

These collections are included in the 1,078 musical factory sounds. Find them under Showcase Banks.

Get Mosasaur Mono 1.30.101 and the guides ↗

YOUR NEXT SOUND STARTS HERE

Meet Mosasaur.

1,078 factory presets. Deep sound design.
A free synthesizer for curious ears and hands-on exploration.
Version 1.30.101 · AU, VST3 and standalone.

FREE MONO EDITION / APPLE SILICON / macOS 13+

Mosasaur Mono 1.30.101

AU, VST3 and standalone, with both sound-design layers and all 1,078 musical factory sounds. The installer includes both guides.

Get Mono and the guides ↗
22-page illustrated Quick Start PDF ↓216-page complete user guide PDF ↓

A LITTLE HELP, WHEN YOU NEED IT

Keep exploring.

Find a control, work through a question,
or tell us what isn’t behaving as expected.

01
Ask about Mosasaur

Guides and direct email support.

↗02
Report a problem

Help us make the next build better.

↗

Contact Michael by email, or prepare a problem report to send.

STAY IN THE LOOP / OPTIONAL

More sounds.
When they're ready.

Release news, new sound banks and occasional tips. No account or email address needed to download Mosasaur.

INDEPENDENT BY NATURE

Made by a curious ear.

Michael Gager

Creator
Chief Executive Mosasaur

The Mosasaur monosynth is free and always will be. If it earns a place in your projects, you can buy me a coffee — support goes toward development tools and expanding what the next version can do.

Buy Me a Coffee
Sound
Expanded Mosasaur Sound interface

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