Citadel Alchemist
Bastl Instruments 16HPPatchable hybrid-synthesis voice with MIDI, tempo-synced pattern generation, dual FX and stereo I/O. Monophonic but heavily modulatable, it doubles as a voice, rhythm source and MIDI bridge.
Patch Ideas · 5
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Behaviors
The voice moves through FILTER, FM, HYPERSINE, SUPERSAW and GLITCHNOISE while the ratio and envelope macros reshape how the mode behaves.
The internal quantizer holds the current scale, updates notes on trigger and can preview octave and root changes through bank combinations.
The built-in pattern engine generates CV and gate streams that can be synced, reset and customized from the web editor.
The LFO can sync to clock, reset to phase zero or free-run, which makes the module behave like a small self-contained groove engine.
The module can process external stereo audio through its dual effects section and return it as a stereo voice or modulation source.
The module receives clock and notes over TRS MIDI and sends or receives USB MIDI on the rear connector.
Controls
| Voice | PITCH | Sets the core pitch in a ±3 octave range from the base note. macro knob |
| Voice | PITCH MOD | Attenuverts incoming pitch modulation. attenuverter |
| Voice | TIMBRE | Sweeps the sound engine across the five synthesis modes. FILTER · FM · HYPERSINE · SUPERSAW · GLITCHNOISE |
| Voice | TIMBRE MOD | Modulates timbre with bipolar depth control. attenuverted CV |
| Voice | RATIO | Sets oscillator detune ratios and waveform blend relationships. macro knob |
| Voice | ENV | Shapes the envelope behavior and pushes the sound toward drone, body or transient focus. macro knob |
| Voice | ENV MOD | Attenuverted envelope modulation input. updates on trigger |
| LFO | LFO FREQUENCY | Sets the built-in LFO rate. syncable or free-running |
| LFO | LFO MOD | Sets depth and polarity for LFO modulation. attenuverter |
| Voice | MODE | Selects the synthesis mode or morph target. CV-capable |
| Global | SHIFT | Secondary action button for triggering and alternate panel functions. momentary |
| Clock | TAP TEMPO | Sets the internal tempo generator. tap-tempo |
I/O
IN · 15
- NOTE IN -0.2V to 7V GATEQuantized pitch input; updates on trigger and follows the selected scale.
- PLAY IN 3V+ trigger GATEQuantized pitch trigger input for the arpeggio-style upper voices.
- PITCH MOD -5V to +5V CVPitch modulation input with attenuverter.
- TIMBRE MOD -5V to +5VModulates the timbre sweep.
- MODE IN -5V to +5V CVCV-selects or morphs the synthesis mode.
- ENV MOD -5V to +5V ENVModulates the envelope macro.
- LFO RESET 0V to 5VResets the internal LFO phase.
- CLK IN 0V to 5V CLKExternal tempo clock input.
- RESET IN 0V to 5VResets the internal pattern generator.
- C IN -5V to +5VAuxiliary control input for the pattern engine.
- G IN 0V to 5V GATEAuxiliary gate input for the pattern engine.
- TRIGGER IN 0V to 5V GATETriggers the sound engine.
- L/R IN -10V to +10V AUDIOStereo audio input for processing through the internal mixer and effects.
- TRS MIDI IN MIDI CLKFront-panel TRS MIDI input for clock, notes, CC and pitch bend.
- USB-C USBRear USB-C port for firmware updates, USB MIDI in/out and sample upload.
OUT · 8
- CLK OUT 0V to 5V CLKTempo output from the internal clock generator.
- ENV OUT 0V to 5V ENVPatchable envelope output.
- CV OUT 0V to 5V GATEGate-pattern CV output from the sequencer engine.
- LFO TRI OUT 0V to 5VTriangle LFO output.
- LFO PULSE OUT 0V to 5V GATEPulse LFO output.
- L/R OUT -5V to +5V AUDIOStereo DC-coupled audio output.
- HEADPHONE OUT 2VppFront-panel headphone output.
- SYNC OUT 0V to 5VAnalog sync output.