A sound designer's dream.
A friendly, open community.

Featuring many synthesis techniques, a great selection of filters, a flexible modulation engine, a smorgasbord of effects, and modern features like MPE, microtuning (with MTS-ESP support!), and comprehensive Open Sound Control (OSC) support.

Surge XT is a wonderful tool. We love it. We think you will, too!


Latest release: Surge XT 1.3.2 (2024-05-08 14:52:53 UTC )

Downloads for other platforms and installers

Learn more about the CLAP standard

Read the manual

Surge XT ports maintained by other projects

Roger Linn demonstrates Surge on his Linnstrument

Surge XT Videos

We have a collection of great demos on our YouTube channel.

Explore the videos!

One Synth Challenge,
Thank YOU!

We think it's pretty cool that you picked Surge XT for the One Synth Challenge. And then did it again a few more times!

Surge XT was in the spotlight of OSC #122, #138, #159, and most recently, #181. A talented group of musicians created all these tracks using Surge XT as the only sound generating device. Or - in some exceptional cases - only Surge XT Effects plugin was used, much to our awe and amazement!

Do give these tracks a listen, as we think they are a brilliant showcase of flexibility and amazing range of sounds that Surge XT offers.

Digital Beauty
Surge XT is a digital synth and makes no bones about it.

If you have used it in the past, it will be like welcoming an old friend back into your life. If you are new to Surge XT, welcome to the party. Come on in, the water is fine.

Surge is back, XTended and open source!

Thanks to the generosity of @Kurasu (owner of Vember Audio), Surge has been open sourced and lives on GitHub. This page you're reading right now. Yup! This one right here. It's a part of the surge-synthesizer GitHub project.

Synthesis method: Subtractive hybrid

Each patch contains two scenes which are separate instances of the entire synthesis engine (except effects) that can be used to create layered or split patches.

Quick category-based patch browser with textual search and favorites.

Runs on a variety of operating systems, plugin formats, and architectures.

Factory Sounds

Over 2800 patches

Over 700 wavetables


3 oscillators per scene, with 12 versatile oscillator algorithms: Classic, Modern, Wavetable, Window, Sine, FM2, FM3, String, Twist, Alias, S&H Noise and Audio Input.

Classic oscillator is a morphable pulse/saw/dual saw oscillator with a sub-oscillator and hard sync.

Modern oscillator is a mixable saw/pulse/triangle oscillator with an optional sub-oscillator mode for triangle (which can also change to sine or square) and hard sync.

FM2/FM3 oscillators consist of a carrier and 2 or 3 modulators and various options.

String oscillator uses two filtered waveguides to emulate plucked or bowed string sounds.

Twist oscillator is based on a very famous Eurorack macro oscillator, and it offers a myriad of synthesis options in a very simple and quick way.

Most algorithms (except FM2, FM3, Twist and Audio Input) offer up to 16-voice unison at the oscillator level.

Oscillator FM in 3 different configurations and ring modulation between oscillators 1-2 and 2-3.

Most oscillator algorithms (except FM2, FM3, Sine and Alias) are strictly band-limited, yet still cover the entire audible spectrum, delivering a clear, punchy and clean sound.

Noise generator with variable spectrum (available directly in the oscillator mixer).

Filter Block

Two filter units in 8 different configurations, with feedback loop available in 7 of them.

Available filter algorithms: Lowpass (12 and 24 dB/oct, each with 3 variations), Legacy Ladder Lowpass (6-24 dB/oct), Vintage Ladder Lowpass (2 variations, each with and without gain compensation), Highpass (12 and 24 dB/oct, each with 3 variations), Bandpass (12 and 24 dB/oct, each with 3 variations), Notch (12 and 24 dB/oct, each with 2 variations), Allpass (3 variations), Comb (positive and negative), S&H.

Open-source additions to our filter algorithms include: K35 and Diode Ladder filter types from Odin 2 synthesizer, 12 and 24 dB/oct multimode filters from OB-Xd, and weird but fascinating Cutoff Warp, Resonance Warp and Tri-Pole filters by Jatin Chowdhury!

Filters can self-oscillate (with excitation) and respond amazingly fast to cutoff frequency changes.

Waveshaper (43 shapes)


12 LFO units available, 6 are per voice and 6 are global for the whole scene.

DAHDSR envelope generators on every LFO.

LFO shapes consist of 7 deformable LFO waveforms, step sequencer, a fully-fledged multi-segment envelope generator (MSEG) with various curves and up to 128 nodes, and last but not the least - a formula modulator which utilizes Lua scripting language to provide completely custom modulator output.

Voice LFOs allow envelope retriggering in step sequencer mode.

Extremely fast and flexible modulation routing. Almost every continuous parameter can be modulated!


16 effect units arranged as 4 inserts per scene, 4 sends and 4 master effects.

27 effect algorithms:

  • 3-band fully parametric EQ
  • 11-band graphic EQ
  • Exciter
  • Resonator
  • Combulator
  • Frequency Shifter
  • Nimbus
  • Ring Modulator
  • Treemonster
  • Vocoder
  • Chorus
  • Ensemble
  • Flanger
  • Phaser
  • Rotary Speaker
Time & Space:
  • Delay
  • Reverb 1
  • Reverb 2
  • Spring Reverb
  • Airwindows (itself containing 56 effects!)
  • Conditioner
  • Mid-Side Tool
Contributors Welcome!

Surge XT is supported by a community of volunteer open source developers, designers, testers, musicians, synthesizer enthusiasts, and content creators.

Without them, none of would have been possible. If you're interested in seeing what's going on with the project, the best thing to do is:

View the Surge XT Repository

If you are interested in contributing, we welcome developers who know or want to learn C++, git, graphics and Web design.

There's plenty of open issues and our Discord server can help you find a good first one if you want. Hop over to the Issues page on GitHub to see what we need help with.

View Surge XT Issue Tracker

You can also join the conversation in #surge-development channel at the Surge Synth Team Discord server. We'll help get you started!

Join Surge Synth Team Discord Server

If you would like to pitch in and have interests in UX, UI, visual design or any other design related topics, there are plenty of open issues.

The #surge-design channel on Surge Synth Team Discord server can help you find something to get started with.

Join Surge Synth Team Discord Server

Know any testers? Umm, asking for a friend.

Testing is a way that everyone can help contribute. All you would need to do is install a copy of Surge XT and use it in your own workflow.

There are so many combinations of operating systems and DAWs that it is really difficult to make sure everything gets tested under all contexts.

If you would like to get involved, jump in over here:

View Surge XT Issue Tracker
Content Creators

If you love to use Surge XT and make amazing presets or music, we want to hear from you!

In fact, we would love to have you pitch in and help out with the project!

We are looking for people that have content which showcases Surge XT in all of its glory.

If you make patches, write entire songs using only Surge XT or anything in between, we would love for you to be involved!

Join Surge Synth Team Discord Server

We love Surge XT. We also love people.

Community is a big thing to us on this project. We want an inclusive, positive, and happy community with contributions from a large set of differing viewpoints and backgrounds.

Let's be kind to each other and treat each other with respect. It takes all of us working together to make the community great.

We are looking forward to your insights and contributions.

Let's make something amazing!

~Surge Synth Team

Get Involved Here
System Requirements
  • Minimum: Windows 7 and Intel or AMD processor featuring SSE2 instructions
  • Recommended: 64-bit Windows 7 or newer, 3 GHz quad-core processor featuring SSE2 instructions or better
  • Minimum of 4 GB of RAM
  • VST3 or CLAP compatible host application
  • x64-compatible CPU, OS and host is required to use the 64-bit version
  • Surge XT is an Intel/Apple Silicon universal binary. Intel Mac requires macOS 10.11 or later, Apple Silicon Mac will run Surge XT with any Apple Silicon version of macOS
  • Minimum of 4 GB of RAM
  • VST3, AU or CLAP compatible host application
  • PC or ARM system running a Linux distribution
  • x64-compatible CPU, OS and host is required to use the 64-bit version; for ARM processors you can build Surge XT for ARM on Raspberry Pi and similar (tested with RPi4/arm64)
  • Minimum of 4 GB of RAM
  • VST3, CLAP or LV2 compatible host application

This project is maintained by the community at the surge-synthesizer open source project on GitHub.

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