Doepfer A-156 Quantizer
Dual CV quantizer for scales, chords, and melodic grids
8 HP Eurorack module
The A-156 is a dual control voltage quantizer that converts any incoming analog voltage into the nearest musically useful stepped voltage, snapping free-running CVs to scales, chords, or intervals. Quantizer 1 offers a straightforward semitone grid while Quantizer 2 provides elaborate grid settings including major/minor scales, chords, fundamental+fifth, and optional sixth or seventh additions. A shared transpose input simultaneously shifts both quantizer outputs by a quantized semitone amount, making it ideal for generative melodic work, arpeggio-like patterns, and Theremin-style pitch correction.
Features
- Dual independent quantizer channels
- Quantizer 1: semitone (chromatic) grid by default, 1/12 V steps
- Quantizer 2: elaborate grid settings — major/minor scale, major/minor chord, fundamental+fifth, with optional sixth or seventh addition
- Jumper J1 on circuit board allows Quantizer 1 to share the same grid settings as Quantizer 2
- Trigger inputs for synchronizing quantization to external events (LFO, sequencer clock, MIDI clock)
- Quantization occurs at low/high transition of trigger signal when trigger input is used
- Internal quantizing rate of approximately 500 Hz when trigger input is unpatched
- Trigger outputs emit a 10ms pulse whenever a new quantization step occurs (output voltage changes)
- Re-triggering: if a new trigger is needed within the 10ms pulse window, a 5ms pre-pulse appears before the next 10ms pulse
- Shared transpose CV input simultaneously transposes both quantizer outputs
- Transpose CV is quantized to the nearest semitone before being added to both outputs
- Example: +1.0 V at Transpose input shifts both outputs one octave up
Controls & Jacks (25)
- Quantizer 1 CV In — Control voltage input for Quantizer 1 to be quantized
- Quantizer 1 CV Out — Quantized control voltage output from Quantizer 1
- Quantizer 1 Trigger In — Trigger input to synchronize quantization of Quantizer 1 to external events
- Quantizer 1 Mode
- Quantizer 2 CV In — Control voltage input for Quantizer 2 to be quantized
- CV
- Quantizer 1 Trigger Out — Trigger pulse output whenever quantization occurs on Quantizer 1
- Quantizer 2 CV Out — Quantized control voltage output from Quantizer 2
- Quantizer 1 Scale Type — 3-position switch to select scale type for Quantizer 1: chromatic (All), major, or minor
- Quantizer 2 Sixth/Seventh — 3-position switch to add sixth (+6) or seventh (+7) interval to chord/quint modes, or neither (-)
- Switch 1 (Quantizer 1) — 3-position switch to select scale type for Quantizer 1: chromatic (All), major, or minor
- Switch 2 (Quantizer 1) — 3-position switch to select output mode: Scale (all notes of selected scale), Chord (specific chord tones), or Quint (fundamental and fifth
- Switch 3 (Quantizer 1) — 3-position switch to add sixth (+6) or seventh (+7) interval to chord/quint modes, or neither (-)
- Switch 1 (Quantizer 2) — 3-position switch to select scale type for Quantizer 2: chromatic (All), major, or minor
- Switch 2 (Quantizer 2) — 3-position switch to select output mode: Scale (all notes of selected scale), Chord (specific chord tones), or Quint (fundamental and fifth
- Switch 3 (Quantizer 2) — 3-position switch to add sixth (+6) or seventh (+7) interval to chord/quint modes, or neither (-)
- CV In 1 — Control voltage input for Quantizer 1 to be quantized
- CV Out 1 — Quantized control voltage output from Quantizer 1
- Trig. In 1 — Trigger input to synchronize quantization of Quantizer 1 to external events
- Trig. Out 1 — Trigger pulse output whenever quantization occurs on Quantizer 1
- CV In 2 — Control voltage input for Quantizer 2 to be quantized
- CV Out 2 — Quantized control voltage output from Quantizer 2
- Trig. In 2 — Trigger input to synchronize quantization of Quantizer 2 to external events
- Trig. Out 2 — Trigger pulse output whenever quantization occurs on Quantizer 2
- Transpose CV In 1+2 — Control voltage input for simultaneous transposition of both Quantizer 1 and 2 outputs by semitone increments
How-To Guides
- LFO Arpeggio with Minor Seventh
- Analog Sequencer with Exact Tuning
- Auto-Transposing Sequence with Dual Sequencer
- Theremin Pitch Correction to Scale
- Random Generative Melody in a Scale
- Dual Voice Harmony
- Envelope-Controlled Quantized Pitch Sweep
- MIDI Keyboard Real-Time Transposition
- Fundamental and Fifth Drone/Bass
- Clock-Synced Scale Walking Bass Line
Explore the interactive A-156 Quantizer panel on BleepDex — tap any control to learn what it does.
