ALM Busy Circuits TAZM-O
Analog thru-zero FM oscillator with morphing shape and sub octaves
12 HP Eurorack module
The TAZM-O is an analog triangle core oscillator featuring through-zero frequency modulation. It combines a continuous morphing wave shape control (inspired by the Serge NTO), dual SH-101 style sub octave outputs, voltage controlled FM Index, a built-in output VCA, and voltage controlled octave transposition. The primary shape output morphs between sine/triangle, saw, and pulse waves before passing through the integrated VCA. Additional dedicated outputs provide direct sine (or triangle), saw, and two sub-octave pulse signals. An LFO mode lowers the frequency range for modulation duties.
Features
- Analog triangle core oscillator with through-zero frequency modulation
- Continuous morphing wave shape: sine/triangle → saw → variable pulse (10-90% duty cycle)
- Shape control inspired by the Serge NTO
- Built-in linear output VCA with CV control on the primary Shape output
- Dedicated simultaneous outputs: sine (or triangle), saw, sub-1, sub-2, and shape
- Dual sub-octave pulse outputs (SH-101 style): Sub-1 at -1 oct, Sub-2 at -2 oct
- Voltage controlled FM Index for easy dynamic FM patching
- Octave transpose CV input (0/+1/+2 octaves, similar to Akemie's Castle)
- Hard sync input for classic timbral effects
- LFO mode (0.1Hz-30Hz) with bipolar LED indication
- Rear PCB switches: sine/triangle selection, Sub-2 duty cycle (50%/75%)
- V/Oct tracking across ~8 octaves with rear calibration trimpots
Controls & Jacks (22)
- V/Oct — 1V/octave pitch CV input, ~8 octave range
- Coarse Tune — Coarse frequency control, ~7 octave range
- LFO LED Green — Indicates negative sine polarity in LFO mode
- LFO LED Red — Indicates positive sine polarity in LFO mode
- LFO — Latching button to activate LFO mode (0.1Hz-30Hz range)
- TZFM — Through-zero frequency modulation input, routed via internal index VCA
- Fine Tune — Fine frequency control, ~1 octave range
- FM Index — Controls depth of through-zero FM via internal VCA
- Shape — Continuous morphing: sine/triangle → saw → pulse (10-90% duty cycle)
- FM Index CV In — CV input for FM index depth (0-5V), with attenuator
- FM Index CV Attenuator — Attenuator for FM Index CV input (0-5V)
- Shape CV Attenuator — Attenuator for Shape CV input (0-5V)
- Level — Controls built-in linear output VCA level; functions as attenuator when CV patched
- Oct — Octave transpose CV input: ~1V = +1 oct, ~3V = +2 oct
- Sync — Hard sync input, resets oscillator core on rising edge
- Shape CV In — CV input for waveform shape modulation (0-5V), with attenuator
- Level CV In — CV input for output VCA level (0-5V)
- Sine Out — Dedicated sine (or triangle, via rear switch) output
- Sub-1 Out — Sub octave -1, fixed 50% duty cycle pulse
- Sub-2 Out — Sub octave -2 pulse, 50%/75% duty cycle via rear switch
- Saw Out — Dedicated sawtooth wave output
- Shape Out — Primary morphing waveform output through built-in VCA
How-To Guides
- Basic Pulse Width Modulation
- Dual Oscillator FM Voice
- Self-Patched Shape Modulation
- Self-Patched Amplitude Modulation
- Hard Sync Timbral Sweep
Explore the interactive TAZM-O panel on BleepDex — tap any control to learn what it does.
