Doepfer A-196 PLL
Phase Locked Loop for frequency tracking and harmonic chaos
8 HP Eurorack module
The A-196 PLL is a Phase Locked Loop module consisting of an internal VCO, three selectable phase comparators, and a low-pass filter working together in a closed feedback loop to lock the internal VCO to an external signal's frequency. Musically it produces frequency multiplication, portamento-like frequency gliding, harmonic locking, wobbling pitches, and clock generation for graphic VCOs and switched capacitor filters — making it a highly experimental and unpredictable sound design tool.
Features
- Internal VCO with linear CV response and rectangle output
- Three selectable phase comparators: XOR (PC1), RS Flipflop (PC2), complex digital network (PC3)
- Internal low-pass filter with manually adjustable frequency control
- Normalled sockets for standard closed-loop PLL operation without patching
- Normalled sockets can be broken by inserting patch cables to allow custom routing
- LED lock indicator active when PLL is locked in PC2 mode
- Three VCO frequency ranges (low, mid, high) with offset control for maximum frequency
- VCO CV input normalled to LPF output for closed-loop operation
- VCO Out normalled to PC In 1 for internal feedback
- PC Out normalled to LPF input for standard signal chain
- Insert points allow external modules (e.g. frequency dividers, VCF) to be inserted into the loop
- Supports frequency multiplication when combined with external frequency divider (e.g. A-163)
Controls & Jacks (23)
- Low Pass Filter Frequency — Adjusts the cutoff frequency of the internal low-pass filter
- VCO Offset — Sets the maximum frequency of the VCO within the selected range
- VCO CV In
- VCO Out — VCO output with rectangle waveform; connected internally to phase comparator input 1
- PC In 1 — Phase comparator output; digital signal internally connected to low-pass filter input
- PC In 2 (Signal In) — Three-position frequency range switch for the VCO (low, mid, high)
- PC Out — Low-pass filter output; generates smooth control voltage for VCO; internally normalized to VCO CV input
- Phase Comparator Type — Three-position switch to select phase comparator type (PC1: Exor, PC2: RS Flipflop, PC3: digital network)
- Lock — Indicates when the PLL is locked (internal VCO frequency matches external signal frequency)
- In 2
- Low Pass Filter Out
- Out (PC) — output jack
- Offs. — Sets the maximum frequency of the VCO within the selected range
- Range — Three-position frequency range switch for the VCO (low, mid, high)
- Type — Three-position switch to select phase comparator type (PC1: Exor, PC2: RS Flipflop, PC3: digital network)
- Frequ. — Adjusts the cutoff frequency of the internal low-pass filter
- VCO Range — Phase comparator input 2; external PLL signal input (e.g., from A-110 VCO or frequency divider A-163)
- CV In — Control voltage input for the VCO; receives filtered CV from the low-pass filter
- Out (VCO) — VCO output with rectangle waveform; connected internally to phase comparator input 1
- In 1 — Phase comparator input 1; normalized to internal VCO output
- In 2 (Signal In) — Phase comparator input 2; external PLL signal input (e.g., from A-110 VCO or frequency divider A-163)
- Out (LPF) — Low-pass filter output; generates smooth control voltage for VCO; internally normalized to VCO CV input
- LED — Indicates when the PLL is locked (internal VCO frequency matches external signal frequency)
How-To Guides
- Basic PLL Frequency Lock
- Frequency Multiplication with A-163
- Harmonic Locking with PC1
- PLL Portamento Effect
- Frequency Wobble and Jitter
- Standalone Rectangle VCO
- Graphic VCO Clock Generation with A-155
- Insert External VCF into VCO Feedback Loop
- PC3 Experimental Chaos
- Slowly Wobbling Drone via LFO Input
Explore the interactive A-196 PLL panel on BleepDex — tap any control to learn what it does.
