Sample Banks

Strudel sample banks

The studio registers the current official Strudel default sample maps before the editor becomes ready. Audio comes from a local mirror under storage/sample-banks, outside the public web root. Samples are decoded on first use; opening the studio does not download the whole collection into the browser.

The installed snapshot (2026-10-02) contains 1,063 sound names and 6,325 distinct audio files, totaling 3,047,281,013 bytes. The sound count includes the original XXC samples and excludes additional bank aliases and synthesized sounds. Identical audio is stored once. There are 6,511 upstream file URLs before content deduplication.

Included collections

Collection	Mapped names	Examples
Tidal drum machines	683	RolandTR909_bd, RolandTR808_sd, EmuSP12_bd
Dirt-Samples	218	breaks125, casio, crow, jazz, numbers
VCSL	128	ballwhistle, bassdrum1, orchestral/percussion instruments
Uzu drumkit	16	bd, sd, hh, cp, rim, misc
Mridangam	13	mridangam_ta, mridangam_gumki
Uzu wavetables	7	wt_digital, wt_digital_bad_day
Salamander piano	1 pitched instrument, 29 recordings	piano
XXC originals	7	xxc_bd, xxc_sd, xxc_hh, xxc_oh, xxc_cp, xxc_rim, tone

Some collection names overlap, so the total is not the sum of this table. The complete Dirt collection loads first. The current official default maps then take precedence. In particular, bare bd, sd, hh, cp, rim, and misc come from Uzu, matching the current official defaults. The earlier procedural drums remain available with the xxc_ prefix. xxc_wt remains the original procedural wavetable.

The upstream bank aliases are registered too: .bank("TR909") and .bank("RolandTR909") resolve the same recordings. crackle, pink, white, and brown are official SuperDough noise synths, not missing sample files.

Usage

No samples() call is necessary for default sounds:

setcpm(128/4)
$: s("bd*4").bank("RolandTR909")
$: s("hh*16").bank("RolandTR909").gain(".5 .3 .8 .3").swingBy(1/6, 4)
$: s("~ cp ~ cp").bank("RolandTR909").room(0.15)
$: s("rim(5,16)").bank("RolandTR909").gain(0.3).delay(0.2).delaytime(0.1875)
$: s("crackle*2").density(0.03).gain(0.1)

These supplied examples also work unchanged:

speed("1 1.5*2 [2 1.1]").s("piano").clip(1)

s("bd sd [~ bd] sd,hh*16, misc")

External sources still use the official Strudel API:

samples('github:tidalcycles/dirt-samples')
s("breaks125").fit().slice([0,.25,.5,.75], "0 1 1 <2 3>")

An explicit external samples() call can replace previously registered sounds with that source's versions. It fetches directly from the external host, so HTTPS, CORS and that host's availability still apply. The default local banks do not require GitHub or Strudel's CDN to be reachable from the browser.

Open SAMPLES in the right workbench to search names or aliases, filter by collection, audition, favorite and insert sounds. Results are paginated to keep the editor responsive. Collection filters show upstream attribution and published license status.

Banks tab

Open BANKS in the right workbench to browse the installed bank names, short aliases, General MIDI instruments and custom banks loaded by your score. Search matches bank names, aliases, collections and individual voices.

• Insert .bank() inserts a modifier such as .bank("RolandTR909") at the editor cursor, replacing any selection.
• Name inserts only the bank name, useful inside an existing quoted value.
• Example inserts a complete pattern using a voice from that bank.
• Expand Browse voices and click a voice to insert its pattern. General MIDI and wavetable examples include a starting note.
• After loading a custom sample map, click Refresh banks to include its registered sound names.

Insertions use the editor's normal undo history. The browser reads names from the isolated runtime; sample URLs and credentials are not passed to this panel. Default / unbanked groups sounds used without a bank prefix. Banks follow Strudel's bank_voice naming convention.

Reproduce the installation

python3 scripts/install-sample-banks.py
./scripts/build.sh

The first command installs or repairs from the committed maps and SHA-256 audio lock. It reuses verified files. The build runs --check, verifies every local byte hash without networking, and regenerates the public metadata. A new server needs approximately 3 GB for these banks plus at least 2 GiB free for application storage. FFprobe must be installed.

python3 scripts/install-sample-banks.py --check
python3 tests/sample-banks-http.py
npx playwright test tests/e2e/sample-banks.spec.ts

The downloader uses up to eight workers, bounded files, retries, inspected audio streams, atomic writes and an installation lock. It first uses Strudel's CDN, then a pinned upstream Git revision. A hash mismatch fails installation. Source maps and revisions are in config/sample-banks/; the source repository stores metadata and hashes, not the 3 GB of recordings.

For an intentional catalogue update, first review and update sources.json, maps/, aliases.json, fallbacks.json and the notices. Then run python3 scripts/install-sample-banks.py --update-lock. This is a maintainer operation, not part of normal builds. Existing installed files remain until explicitly removed; the application cleanup job never deletes these banks.

The generated public/sample-banks/runtime.json preserves pitched maps, sample ordering, names and aliases. Vite copies it and the searchable catalogue into html/sample-banks/. All actual audio remains in private storage, served through the read-only /sample-banks/audio/{sha256}.{extension} endpoint. This endpoint supports ranges, HEAD and immutable caching without a session or an arbitrary file path. PHP can read the installed banks but cannot modify them.

Sources and notices

• Official REPL sample registration, inspected 2026-10-02.
• Dough sample maps and official sample documentation.
• Recorded attribution and licenses. Audio licenses are independent of the application's AGPL license.

The browser compatibility suite measures nonzero analyser output for all four supplied examples, the separate 909 voices, alias lookup, noise synthesis, and representatives of the remaining collections. It tests both Chromium and WebKit. The installer inspects every downloaded file with FFprobe and locks its hash; browser decoding of every variant is not claimed.

General MIDI soundfonts

The default soundfont registry contains 125 gm_* instrument names, using the official @strudel/soundfonts@1.3.0 registerSoundfonts() API, as the upstream REPL does. Registration is separate from importing the module. The initial implementation exposed the module but omitted this registration; that caused the reported gm_piano and gm_electric_bass_finger errors. Both now register before the editor becomes ready.

$: note("c4 e4 g4 b4").s("gm_piano")
$: note("c2 ~ g2 ~").s("gm_electric_bass_finger")

These instruments load the chosen soundfont variant from https://felixroos.github.io/webaudiofontdata/sound on first playback through the official loader. No full soundfont library is downloaded at startup or mirrored on this host. They are additional to the 1,063 locally mapped sounds. Variants such as s("gm_piano:1") retain upstream behavior. The SAMPLES browser lists their names and provides insertion.

The default registry and loader were verified against official REPL initialization and the pinned package source. Browser tests play the piano and finger bass individually and together and measure nonzero output in Chromium and WebKit. Remote host availability and CORS still apply to soundfont audio.