NEWS
December 7, 2025
OB-Xd 3.14 released
OB-Xd 3.14 introduces polyphonic unison mode, a major enhancement allowing multiple notes to be played simultaneously with stacked voices per note, unlocking evolving chords and complex textures while maintaining the classic mono unison behavior when needed.

Polyphonic Unison Mode
- Previously unison forced monophonic behavior allowing only one note to sound at a time with all voices stacked in classic mono synth behavior.
- Now unison mode maintains polyphonic behavior where Polyphony Voices controls the number of simultaneous notes you can play and Unison Voices controls how many voices stack per note.
- Classic mono unison still available by setting polyphony to 1 voice for vintage Minimoog-style behavior.
- Play thick chords with unison enabled: stack 2-4 voices per note across 4-8 note chords for massive pads and lush leads.
- Flexible voice budgeting balances thickness vs. polyphony based on your part-thick mono leads or thinner polyphonic textures from the same preset.
Practical Examples
- 8 voices, unison ON, multiply 2: Play 4 notes with 2 stacked voices each = thick chords with moderate detuning.
- 16 voices, unison ON, multiply 4: Play 4 notes with 4 stacked voices each = super-wide stereo pads.
- 8 voices, unison ON, multiply 8: Play 1 note with 8 stacked voices = classic mono unison lead (vintage mode).
- 32 voices, unison ON, multiply 2: Play 16 notes with 2 voices each = complex polyphonic sequences with movement.
User Interface Enhancements
- Polyphony Preset Menu: Replaced linear 1-32 voice count menu with musically meaningful preset values (1, 2, 4, 6, 8, 12, 16, 24, 32) matching classic and modern synthesizer standards.
- First-Time Unison Dialog: Informational dialog appears once when unison is clicked, explaining the new polyphonic behavior and how to achieve classic mono unison.
Technical Implementation
- Simplified voice allocation logic by removing unison/non-unison branch distinction.
- Always uses polyphonic allocation with calculated voices per note group.
- Vectorized architecture processes voice groups efficiently through SIMD instructions (AVX2 on Intel/AMD, NEON on ARM).
- Makes complex polyphonic unison practical on modern CPUs without performance degradation.
This update is free for existing OB-Xd 3.x customers and available now in AAX, AU, VST2, VST3, LV2, and standalone formats for Windows, macOS, and Linux with Universal Binary 2 and native Apple Silicon support. Visit our OB-Xd product page for download information and complete documentation.