Surge uses a subtractive hybrid synthesis algorithm. Each patch contain two 'scenes' which are separate instances of the entire synthesis engine (except effects) that can be used for layering or split patches.
It includes a rich library of factory sounds:
- 1725 patches
- 523 wavetables
- 3 oscillators per scene.
- 8 versatile oscillator algorithms: Classic, Sine, Wavetable, Window, FM2, FM3, S&H Noise and Audio Input.
- Classic oscillator is a morphable pulse/saw/dual saw oscillator with a sub-oscillator and hard sync.
- FM2/FM3 oscillators consist of a carrier and 2 or 3 modulators and various options.
- Most algorithms (except FM2, FM3 and Audio input) offer up to 16-voice unison at the oscillator level.
- Oscillator FM and ring modulation between oscillators 1-2 and 2-3.
- Most oscillator algorithms (except FM2, FM3 and Sine) are strictly band-limited, yet still cover the entire audible spectrum, delivering a clear punchy yet clean sound.
- Noise generator with variable spectrum.
- Two filter units in 8 different configurations.
- Feedback loop available in 7 of those configurations.
- Available filter algorithms: Lowpass (12 and 24 dB/oct, each with 3 variations), Lowpass 24 dB/oct (3 variations), Ladder Lowpass (6-24 dB/oct), 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), Comb (4 variations), S&H.
- Filters can self-oscillate (with excitation) and respond amazingly fast to cutoff frequency changes.
- Waveshaper (5 shapes).
- 12 LFO units available, 6 are per voice and 6 are global for the whole scene.
- DAHDSR envelope generators on every LFO.
- 7 deformable LFO waveforms and step sequencer mode.
- Voice LFOs allow envelope retriggering when used as step sequencer.
- Extremely fast and flexible modulation routing. Almost every continuous parameter can be modulated!
- 8 effect units arranged as 2 inserts per scene, 2 sends and 2 master effects.
- 13 effect algorithms: EQ, Distortion, Conditioner (EQ, stereo image control and limiter), Frequency Shifter, Rotary Speaker, Ring Modulator, Vocoder, Chorus, Phaser, Flanger, Delay, Reverb 1, Reverb 2