Overtonium is Benjamin Dehli's free, open-source 32-partial additive synth, laid out like a mixer, with per-harmonic control and continuous equal-to-just microtuning.
Plugin comparison
Overtonium vs Serum 2
Specs, price and the Dubspot Score, side by side — with our verdict on which synth to buy.
Independent score / workflow fit / buying signal
Contenders
The side-by-side
9.2Essential
Serum 2 is Xfer Records' wavetable synthesizer plugin with five oscillator engines, flexible effect routing, an arpeggiator, and a clip sequencer.
Score verdict
Which should you buy?
On the Dubspot Score, Serum 2 comes out ahead (9.2). That said, the right pick depends on your workflow and budget — read both reviews before deciding.
Technical matrix
Specs compared
| Signal | Overtonium | Serum 2 |
|---|---|---|
| Price | Free | $249 |
| Dubspot Score | — | 9.2 |
| Formats | VST3, AU, LV2, Standalone | VST3, AU, AAX |
| Type | Additive synthesizer (32 partials plus noise) | — |
| Sound source | 32 sine oscillators locked to harmonics, plus a noise channel | — |
| Per-partial control | Around 23 controls per channel strip | — |
| Tuning | Continuous equal-to-just TUNE sweep, inharmonic stretch | — |
| Keyboard temperaments | Equal, just, Pythagorean, quarter-comma meantone, Werckmeister III, Young | — |
| Effects | DRIFT, WOBBLE, dual-path tape echo | — |
| Expression | MPE, per-note pitch bend and pressure | — |
| Formats | VST3, AU (macOS), LV2 (Linux), standalone; macOS, Windows, Linux | — |
| Oscillator engines | — | 5 (Wavetable, Multisample, Sample, Granular, Spectral) |
| Factory presets | — | Over 626 presets |
| Wavetables | — | 288 wavetables |
| Plugin formats | — | VST3, AU, AAX (64-bit) |
| Platforms | — | Windows 10+ and macOS High Sierra+ (Intel) / Big Sur+ (Apple Silicon) |
| Additional tools | — | Arpeggiator, clip sequencer, flexible effect routing |
See the full plugin database for more comparisons.