Sixteen parts
A multi holds 16 parts, each an instrument with its own MIDI channel, macros and four FX. Play several instruments from one instance, or layer and split them.
Open Source Sampling Workstation
Shortcircuit XT
Shortcircuit XT is a modern open source software sampler focused on workflow, expressive modulation, and deep sample playback control.
Highlights
Zones, groups and variants
Map samples across key and velocity, gather zones into groups with their own play mode and trigger conditions, and give a zone up to 16 variants for round robins.
Processors per voice
Every zone has four processor slots that run on each voice, and every group has four more on its mix: filters, distortion, EQ, delays, resonators and synth generators.
Modulation
Each voice runs its own envelopes, LFOs, step sequencers, phasors, randoms and envelope followers through a modulation matrix, alongside 16 macros per part.
Opens your libraries
Import SF2, SFZ, EXS, GIG, Akai AKP and .multisample instruments, and load WAV, FLAC, AIFF, MP3 and Opus samples.
Mixer, MPE and tuning
A 21 bus mixer with aux sends and 20 extra stereo outputs, MPE and CLAP note expressions, and microtuning through MTS-ESP or Scala files.
Manual
The Shortcircuit XT manual covers installing, how a multi is built from parts, groups and zones, each screen of the interface, the mixer and routing, importing other formats, MPE, microtuning and the keyboard shortcuts.
Open ManualChangelog
Latest nightly build updates for Shortcircuit XT. Last build: Oct 21, 2026.
Latest commit: 72ad423Full release notes
Update clap-wrapper to next, for the GCC 12 release build fix
Paul Walker · 72ad423 · Oct 21, 2026
Standalone has an Audio/MIDI Settings menu item, with clap-wrapper 0.17
Paul Walker · 0a90cb0 · Oct 21, 2026
Velocity ranges start at 1
Paul Walker · b21cee6 · Oct 21, 2026
MIDI learn notes now play, and MIDI select works with nothing selected
Paul Walker · f76c9b9 · Oct 21, 2026
Loop crossfade handle sits on its curve and drags one way at a time
Paul Walker · 7cf8602 · Oct 21, 2026
FAQ
Is Shortcircuit XT free?
Yes. It is free and open source. The source is MIT licensed, and released binaries are distributed under the AGPL v3 or later.
Is it finished?
No. Shortcircuit XT is in beta, and the download on this page is a nightly build of the current code. Use a limiter while experimenting.
Which systems and plugin formats are supported?
Windows, macOS 10.15 or later, and Linux. Shortcircuit XT runs as a CLAP or VST3 plugin, as an Audio Unit on macOS, and as a standalone application.
Can it load my sample libraries?
It imports SF2, SFZ, EXS, GIG, Akai AKP and .multisample instruments, and loads WAV, FLAC, AIFF, MP3 and Opus samples. Features a format has that Shortcircuit XT cannot represent are skipped.
Where are my patches kept?
In Documents/Surge Synth Team/Shortcircuit XT, which also holds themes and presets. A whole instrument saves as a .scm multi and a single part as a .scp.
Where do I get help or report a bug?
Ask in the #using-shortcircuit channel of theSurge Synth Team Discord, and report bugs on theissue tracker.
About
Shortcircuit XT is a rebuild of Shortcircuit 1 and 2, samplers released by Vember Audio in the mid 2000s. Claes Johanson, who wrote the originals, gave the Shortcircuit 2 source to the Surge Synth Team, and Shortcircuit XT keeps much of that design and DSP while rewriting the rest in modern C++.
It is developed in the open by the Surge Synth Team, onGitHub and in the#sc-development channel of ourDiscord. The open source projects it is built on are listed in themanual's credits.