Pipe organ sample player for Hauptwerk-format and GrandOrgue sample sets.

masterpiece-hero.mp4

Watch the demonstration — thirty-three works on nine organs, recorded from the application's own output · programme and credits
Watch "New tested instruments" — thirty works on fifteen organs, filmed from the running console · programme and credits

Portable archives for every platform, and the plugins on their own, are on the releases page.

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Masterpiece plays sampled pipe organs. It reads Hauptwerk-format sample sets and GrandOrgue organs, draws each instrument's own console, and plays it from the mouse, a MIDI keyboard or a full console. It is an independent implementation in C++20 and JUCE, licensed GPL-3.0-only.

• Standalone application, VST3 and LV2 plugins, and an Audio Unit on macOS
• Windows, macOS (Apple silicon and Intel), Linux, Raspberry Pi (64- and 32-bit), Android and iPhone/iPad
• Tested on 37 published sample sets, from a 9-register Flentrop to Nancy's 65 stops on four manuals

Features

Sample sets

• Hauptwerk-format definitions, full and compact, read directly
• GrandOrgue .organ definitions, converted as they load, console included
• Sets played straight from their packages: RAR 4 and 5 (solid, multi-part, multi-volume) and GrandOrgue .orgue
• WAV and WavPack samples, any rate; optional conversion to the device rate on load
• Sets that require a publisher's licence load once you confirm you hold it

Console

• The set's own artwork: drawstops, keys, pedals, shoes, jamb pages, several console sizes where a set ships them
• Couplers, sub- and super-octaves, unison off, reversible pistons, crescendo and alternate ranks, all through the set's own switch network
• A stop list grouped by division, for sets drawn across many jambs or shipped as text only
• Any page in its own window, remembered per organ

Sound

• Attack, crossfaded sustain loop, and a release chosen by how long the key was held, with a crossfade into it
• Wind model: chests, bellows and valves solved as a system; a full registration lowers the pressure, and pitch and level follow it
• Tremulants per pipe and per chest; enclosures with level and filter per box
• Hermite interpolation; 1536 voices, stealing releases first
• Optional vectorized engine, AVX2, SSE2 or NEON, 3 to 5 times faster on 512 voices (experimental, off by default)

Memory and loading

• 24-bit resident (bit-identical to the files) or 16-bit; stereo can be folded to mono
• Release tails streamed from disk through per-voice ring buffers; keep the first second or 25, 50 or 75% of each release in memory
• Leave out stops, perspectives or single ranks; left-out stops take their tremulant ranks with them
• Decoded sample cache: a second load reads one cache file
• A memory limit, 80% of RAM by default; a load that reaches it stops and says what to change
• Optionally keep an organ playable after its installation files are removed

Combinations and registration

• Player's own generals (up to 100), divisionals per manual, general cancel, and a 999-frame stepper, on any organ, beside the organ's own pistons
• Named combination sets, saved per organ
• Optional: Set turns off after storing a piston with the mouse

Tuning

• The organ's temperament, equal, or Werckmeister III, Kirnberger III, Vallotti, Young II, quarter-comma meantone, Pythagorean, Silbermann sixth-comma; Scala .scl files
• Pitch in Hz (415, 440, 442 one click away); transposer ±12 semitones
• Voicing: level and tuning per rank and per pipe, with A/B sets to compare

MIDI and consoles

• All inputs at once, each mapped to a manual by channel; key range, transpose, velocity window, short octaves, debounce, split keyboards
• MIDI learn for drawstops, pistons, shoes, pages, stepper and transposer; MIDI out lights a console's drawstops
• Jamb text displays over system exclusive
• A virtual MIDI input on macOS and Linux

Recording and practice

• MIDI recording of notes, stops and shoes, replayable through another registration
• Audio recording alongside; metronome in the organ's own audio stream
• Convolution reverb for sets recorded dry

Limitations

• Encrypted samples (.hbw, .hbx) are skipped and listed in the load report
• GrandOrgue divisional couplers are skipped on import

Measured

Friesach, 44 stops, 17 GB, 12,148 files (method and full figures):

Resident format	Memory
32-bit float	21.6 GB
24-bit	16.2 GB
16-bit, releases streamed	4.65 GB
16-bit mono, releases streamed	2.33 GB

Opening: 77.1 s at 32-bit float, 25.9 s at 16-bit mono streamed, 18.9 s from the sample cache. Streaming assumes SSD-class storage; the status line says when a disk falls behind.

Tested organs

Each set below is a separate, freely published library: 23 by Piotr Grabowski, 14 by Augustine's Virtual Organs. Full credits in ATTRIBUTION.md.

Screenshots of all 37

Lipiny — a historic case, drawstops lettered in Fraktur	Melcer Chamber Music Hall
A. Volkmann, 1898 · 25 stops · sample set by Piotr Grabowski	chamber organ · sample set by Piotr Grabowski
Azzio	Kraków, St. John Cantius
Mascioni, 2016 · 12 stops · sample set by Piotr Grabowski	40 stops, three manuals · sample set by Piotr Grabowski
Długa Kościelna	Raszczyce
22 stops · sample set by Piotr Grabowski	Vermeulen, 1965 · 21 stops · sample set by Piotr Grabowski
Strassburg	Friesach — three manuals, jambs on their own pages
C. Werner, 1743 · 20 stops · sample set by Piotr Grabowski	Eisenbarth, 2000 · 44 stops · sample set by Piotr Grabowski
Nancy — four manuals; the keys are part of the photograph, and the drawstops are colour-coded by division	Lemmer — a Flentrop under the saints, with the recording perspective on the case
65 stops, four manuals · sample set by Piotr Grabowski	Flentrop, 1977–78 · 9 registers · sample set by Augustine's Virtual Organs
Giubiasco	Alessandria — pipes reached through pallet switches
complete set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Pinerolo	Ermelo
demonstration set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Święta Lipka — pipes reached through pallet switches	Nitra
demonstration set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Erfurt-Büßleben	Erfurt, Predigerkirche — pipes reached through pallet switches
demonstration set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Obervellach	Düren
demonstration set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Chorzów, St Hedwig of Silesia	Goch
demonstration set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Oloron-Sainte-Marie	Bégard
demonstration set · sample set by Piotr Grabowski	demonstration set · sample set by Piotr Grabowski
Nagyrákos — an Angster organ	Hungarian village organs — the organs of two village churches in one set
Angster, 1938 · demonstration set · sample set by Augustine's Virtual Organs	composite set · sample set by Augustine's Virtual Organs
Zalalövő — a modern baroque organ	Császár — a Luber organ
Aquincum · demonstration set · sample set by Augustine's Virtual Organs	F. X. Luber, 1793 · demonstration set · sample set by Augustine's Virtual Organs
Vasvár, Dominican church	Kézdimartonfalva — a Dutch harmonium
demonstration set · sample set by Augustine's Virtual Organs	harmonium · sample set by Augustine's Virtual Organs
Szombathely — an Eule organ	Hajós — an Angster organ
Eule · demonstration set · sample set by Augustine's Virtual Organs	Angster · demonstration set · sample set by Augustine's Virtual Organs
Székesfehérvár, Franciscan church — a Mauracher organ	Székesfehérvár, Cistercian church — an Angster organ
Mauracher · demonstration set · sample set by Augustine's Virtual Organs	Angster · demonstration set · sample set by Augustine's Virtual Organs
Ják Abbey — an Angster organ	Monor, Reformed church — a Rieger organ
Angster, 1902 · demonstration set · sample set by Augustine's Virtual Organs	Rieger · demonstration set · sample set by Augustine's Virtual Organs
Budapest, Church of the Holy Spirit
demonstration set · sample set by Augustine's Virtual Organs

Installing

Windows. masterpiece-<version>-windows-setup.exe installs with a Start menu entry; the portable .zip runs from any folder and includes the VST3 plugin.

Debian, Ubuntu, Raspberry Pi OS.

sudo apt install ./masterpiece-0.7.9-linux-amd64.deb     # PC
sudo apt install ./masterpiece-0.7.9-linux-arm64.deb     # Raspberry Pi OS, 64-bit
sudo apt install ./masterpiece-0.7.9-linux-armhf.deb     # Raspberry Pi OS, 32-bit

Runs as masterpiece; the PC package also installs the plugins to /usr/lib/vst3 and /usr/lib/lv2. Other distributions: the .tar.gz archives.

macOS. Move Masterpiece.app to Applications. The build is unsigned; if Gatekeeper reports it as damaged, run xattr -cr /Applications/Masterpiece.app and open it with right-click, Open.

Android, iPhone and iPad. The .apk and .ipa on the releases page are installed directly; see the 0.7.0 release notes.

Running

Open takes a definition, a GrandOrgue .organ file, or a RAR or .orgue package. File managers offer Open with Masterpiece; Masterpiece <file> does the same from a terminal.

Option
--odf <file>	Load this organ at startup
--gui-only	Draw the console only, silent, in a second or two
--log <file>	Write a log, with load timings
--log-midi	Log every MIDI message and where it went
--record-midi <file>	Record the session, saved on quit
--play-midi <file>	Play a MIDI file through the organ
--virtual-midi [name]	Publish a MIDI input (macOS, Linux)

All options: Masterpiece --help and COMMAND-LINE.md. Each session writes masterpiece.log in the settings folder; attach it to bug reports.

Audio on Windows: WASAPI exclusive or ASIO for low latency; shared mode adds noticeable delay. On Linux: ALSA and JACK (including PipeWire's JACK); JACK is listed when a JACK library is installed.

Building

C++20 (MSVC 2022, GCC 12+, Clang 14+), CMake 3.22+, Ninja. JUCE, pugixml and the archive libraries are fetched by CMake.

• Debian, Ubuntu, Raspberry Pi OS:

  sudo apt-get install -y build-essential git cmake ninja-build pkg-config \
    libasound2-dev libx11-dev libxrandr-dev libxinerama-dev libxcursor-dev \
    libxcomposite-dev libfreetype6-dev libfontconfig1-dev libglu1-mesa-dev \
    mesa-common-dev libxi-dev libjack-jackd2-dev

• macOS: xcode-select --install, then brew install cmake ninja.
• Windows: Visual Studio 2022 Build Tools with Desktop development with C++; build from the x64 Native Tools prompt.

cmake --preset dev
cmake --build --preset dev

CI presets: ci-linux, ci-macos, ci-windows, ci-linux-arm (32-bit Raspberry Pi cross-build).

Tests run on the small organs in tests/fixtures, in seconds:

cmake --build --preset dev --target mp_tests
build/dev/tests/mp_tests --no-perf

Releasing: cmake/set-version.sh <version>, merge, then tag v<version>; the release workflow builds and publishes every platform.

Layout

mp_core      definition loader, GrandOrgue import, validator, temperaments
mp_sampler   voice engine, release streaming
mp_control   key flow, couplers, switch network, pistons, stepper, crescendo, wind
mp_archive   RAR and .orgue packages, read in place
mp_dsp       enclosure filters, tremulant modulation
mp_audio     audio processor, sample storage, cache, routing
mp_ui        console, settings, MIDI learn

mp_core, mp_sampler, mp_control and mp_archive are plain C++20 and pugixml, so the musical path is tested against synthesised tones.

Credits

Written with four projects as references: GrandOrgue (voice engine, release crossfades), OdfEdit (the definition format), rusty-pipes (samples, loops, file formats) and HISE (streaming through per-voice buffers). Sample sets and MIDI sequences: ATTRIBUTION.md.

Licence

GPL-3.0-only, with an additional permission for combining it with JUCE and UnRAR under their own licences: LICENCE, COPYING. Contributing: CONTRIBUTING.md.

The Windows build includes ASIO support, used under the GPL option of the Steinberg ASIO SDK. ASIO is a trademark of Steinberg Media Technologies GmbH. Hauptwerk is a trademark of its owner. Masterpiece is an independent project.