Surge XT is a virtual synthesizer 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.

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

Surge XT is accessible on Windows and macOS and works well with screen readers.

Oscillators

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.

Modulation

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!

Effects

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

Filtering:

3-band fully parametric EQ
11-band graphic EQ
Exciter
Resonator

Distortion:

CHOW
Distortion
Neuron
Tape
Waveshaper

Mangling:

Combulator
Frequency Shifter
Nimbus
Ring Modulator
Treemonster
Vocoder

Modulation:

Chorus
Ensemble
Flanger
Phaser
Rotary Speaker

Time & Space:

Delay
Reverb 1
Reverb 2
Spring Reverb

Multieffects:

Airwindows (itself containing 56 effects!)
Conditioner
Mid-Side Tool

System Requirements

Windows

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

macOS

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

Linux

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

SURGE XT | VST/AU INSTRUMENT