Web Synth Tools · ESTAMPIE

Quick start

Return to the web synth and press Switch on. Controls that affect the running instrument remain disabled until it has started.
Open MIDI, saves, audio & display below the instrument.
Choose only the tools you need. MIDI preferences and the synth’s ordinary browser save are remembered on this device.

Nothing in this box writes to a connected FM-1. These controls belong to the browser synth. Use the separate web editor for hardware backups and editing.

MIDI

Play notes

Connect your MIDI controller before or after switching on the synth.
Enable MIDI in and allow MIDI access when the browser asks.
Play normally. Messages on all MIDI channels are passed to ESTAMPIE.

Velocity affects incoming Note On messages only. Choose Keyboard velocity to preserve the controller’s dynamics, or a fixed value to make every external note equally strong. Fixed 100 matches the FM-1’s built-in keys.

Control the drawn panel

Enable Panel CC mapping, then assign the CCs below in your controller’s editor. These mapped messages operate the control currently shown on the ESTAMPIE screen—just like touching the corresponding knob or button. Other CCs continue to reach ESTAMPIE’s direct parameter map.

Knobs

CC	Control	Send

Buttons

CC	Control	Send

Absolute 0–127 is the usual choice for standard knobs. The first value establishes the knob position without jumping; later values turn it. Choose Relative 1 / 127 when an endless encoder sends 1 clockwise and 127 counter-clockwise. MASTER is always absolute.

Button combinations with MIDI notes: hold a mapped layer button—FX, GLO, SCL, EDIT, SEQ or REC—then play notes F3 through G5. Those notes act as the FM-1’s 27 physical keys until released, so combinations such as FX + B work from a MIDI keyboard. Notes outside that range continue to play normally.

Buttons need both edges. Configure each button to send a high value when pressed and 0 when released. A toggle-only controller can leave a panel button held.

Portable saves

The emulator already remembers its flash in this browser. A portable state file is different: it lets you keep a dated copy, move work to another browser or device, and maintain more than the four visible project slots.

Export state

Switch on the synth.
Press Export state.
Keep the downloaded .json file somewhere backed up.

The file includes the live session plus saved projects, user sounds, settings and other emulator storage.

Import state

Press Import state and select a ESTAMPIE state file.
Read the replacement warning and confirm.
The page validates the file, installs it and restarts.

Malformed data, bad checksums and invalid live projects are rejected before replacement.

Undo an import

Immediately before an import, ESTAMPIE keeps one recovery copy of the state it is replacing. Press Undo last import to restore that copy. A later import replaces the recovery copy, so export important work rather than treating Undo as a backup history.

Browser storage is not a backup. Clearing site data, using private browsing, changing browsers or losing the device can remove the automatic save. Export state files regularly.

Record audio

Switch on the synth, prepare the sound or project, then choose FLAC, MP3 or WAV from the Format menu.
Press Record FLAC, Record MP3 or Record WAV. The label follows the selected format.
Perform with the drawn panel, computer keyboard or MIDI controller. The recorder captures the final stereo mix: instruments, effects, ambience and the metronome click.
Press Stop & download. Wait for the finishing message; your browser then saves a timestamped file.

Format	Use it for	Details
FLAC	Lossless masters and archiving	The default. Preserves the 24-bit stereo recording without MP3 loss, usually in a smaller file than WAV.
MP3	Sharing and convenient playback	High-quality variable bitrate. Much smaller, but lossy; keep a FLAC or WAV when the master matters.
WAV	Original PCM and broad editor compatibility	Uncompressed 24-bit stereo PCM. It is also the automatic safety format if compressed encoding fails.

The timer advances as audio chunks are secured. The meter shows the highest level reached, in dBFS. If it turns red or the completion message reports clipping, lower MASTER or the track levels and record again.

Local, live and recoverable: audio is encoded entirely in a background worker in this browser and is never uploaded. Recording captures a performance in real time; it does not render a saved project automatically. If the selected compressed encoder cannot start or finish, ESTAMPIE keeps the take and downloads it as WAV instead.

Ten-minute limit: recording stops and downloads automatically at ten minutes. ESTAMPIE retains original PCM during compressed recording so it can make the WAV fallback. A maximum-length take represents roughly 151 MiB at 44.1 kHz or 165 MiB at 48 kHz, plus browser and encoder overhead. On a phone or low-memory device, make shorter takes. Do not close or reload the tab before the download begins.

FLAC and MP3 use self-hosted WebAssembly encoders, so the result does not depend on the browser providing those codecs. FLAC encoding is provided by libFLAC through libflac.js; MP3 encoding is provided by LAME through wasm-media-encoders. Source and licence details are in GHOULBOX’s licensing notes.

Focus Mode

Press Focus screen, or click the FM-1 screen itself, to hide the panel and place the 240 × 240 display against black. This is useful on a phone beside a MIDI keyboard, for projection, or when recording clean screen footage.

Click or tap the enlarged screen to return.
On a keyboard, press Esc to return.
Audio, playback and MIDI continue while the panel is hidden.
If a recording is running, leave Focus Mode before pressing Stop.

Troubleshooting

Controls are disabled

Press Switch on first. Import/export is also disabled while recording or while another file operation is underway.

No MIDI response

Enable MIDI in, grant browser permission, and reconnect the controller. Web MIDI support varies; current Chrome or Edge is the safest choice.

A button stays held

Make the controller send 0 on release, then switch Panel CC mapping off and on to clear held panel controls.

No downloaded file

Check the browser’s download indicator and permission settings. On mobile, the file may appear in the system Files or Downloads app.

Import is refused

Use an unedited state file exported by this emulator. A hardware-editor backup is a different format and cannot be imported here.

The recording clipped

Reduce MASTER or individual track levels until the peak stays below 0 dBFS, then make another take.

I received a WAV instead

The selected FLAC or MP3 encoder could not complete, so ESTAMPIE preserved the take in its original PCM safety format. The status line includes the encoder error.

Finishing takes time

Keep the tab open while the encoder closes the file and the browser prepares the download. Longer recordings and slower phones take more time.

No sound on iPhone or iPad

If the synth reports that audio was paused or interrupted, tap Resume audio. After locking the device or changing apps, you may need to tap it again. If a Home Screen web app remains silent, open ESTAMPIE in a regular Safari tab and switch it on there.

Preferences, saves, recovery data and recorded audio stay on the device running the browser. Only the files you explicitly download leave browser storage.