# Strong-Fundamental Bass Voice Case: **Eurorack 001 Installed** (main rack). Each module is used once. Source: [Learning Modular, Part 4: Osiris Melodic Voice](https://www.patreon.com/LearningModular/posts/my-next-system-4-172357134) Jack names come from the Mutable Instruments manuals, the Mother-32 user manual, and the disting mk4 user manual (v4.18). ## Modules - Moog Mother-32: sequencer, filter, and output - Mutable Instruments Plaits: bass oscillator, with its internal low-pass gate acting as the VCA - Mutable Instruments Stages: short-attack AD envelope on segments 5 and 6 - Doepfer A-180-1: mult for the envelope - Expert Sleepers Disting mk4 (#1): algorithm **B-1 Sample and Hold**, used as a smooth random source - Expert Sleepers Disting mk4 Special Edition (#2): algorithm **A-2 Four Quadrant Multiplier** - Mutable Instruments Shades: attenuates the chaotic envelope before it reaches the filter ## Cables 1. Mother-32 KB (out) -> Plaits V/OCT (in) 2. Mother-32 GATE (out) -> Stages GATE input of segment 5. Patch right to left, as the manual suggests, so segments 5 and 6 form one AD envelope. 3. Stages output 5 -> A-180-1 (any jack) 4. A-180-1 -> Plaits LEVEL (in). This opens the internal low-pass gate, which acts as the VCA. 5. A-180-1 -> Disting #2 Y (in) 6. Plaits OUT (out) -> Mother-32 EXT AUDIO (in) 7. Disting #1 B (out, noise) -> Disting #1 X (in) 8. Mother-32 LFO SQ (out) -> Disting #1 Y (in, S&H trigger). The LFO Square output appears in the manual's output list; the exact panel label is unsure, so check the panel. 9. Disting #1 A (out, smooth random) -> Disting #2 X (in) 10. Disting #2 A (out, random × envelope) -> Shades channel 1 input (jack label unsure, check panel) 11. Shades channel 1 output (unsure, check panel) -> Mother-32 VCF CUTOFF (in) 12. Listen at the Mother-32's main output. ## Starting points - **Plaits:** use the two-operator FM model (the third model in the first bank; per the manual its AUX output is a sub-oscillator). Start with TIMBRE (modulation index) fully CCW for an almost pure sine with a solid fundamental, and HARMONICS at 12 o'clock. - For a lower octave, try the AUX output (the sub-oscillator) instead of OUT. I'm unsure whether the LEVEL/low-pass gate also acts on AUX. If AUX ignores the envelope, set the Mother-32 VCA to EG mode and let its own envelope shape the note. - **Stages:** set segments 5 and 6 to RAMP. Segment 5 is the attack: put the slider near the bottom for a few milliseconds, just enough to avoid clicks, as in Chris's post. Segment 6 is the decay: slider around a third of the way up. - **Mother-32:** - MIX fully toward EXT, so only Plaits feeds the filter and the internal VCO is out of the mix. The manual says patching EXT AUDIO replaces the noise on the clockwise side. - VCF in LOW PASS, CUTOFF around 11 o'clock, RESONANCE low, VCF MOD AMOUNT at 0. - VCA switch in EG mode, with a short attack and long sustain on the Mother-32's EG. - Sequencer: an 8-step bass pattern. - **Disting #1 (B-1):** Z sets the slew; turn it up until the random steps become smooth curves. Set parameter 4 (Atten B) to about half to lower the noise level. - **Disting #2 (A-2):** Z (scale) at 1. - **Shades channel 1:** start around 1 o'clock and raise it until the cutoff wobble is audible but not wild. ## Level notes - **Mother-32 EXT AUDIO:** the manual says it expects a Eurorack-level 10 V peak-to-peak signal at unity gain. If the filter sounds overdriven, lower the Plaits output, for example by lowering the Stages decay level or the Mother-32 MIX. This mirrors Chris's ±8 V clipping problem with the C4RBN. - **Mother-32 VCF CUTOFF:** the manual says this input sweeps the full range with −5 V to +5 V. The disting outputs can swing wider, so keep Shades as the brake. ## What it should sound like A round, solid sub-bass note on every step. The filter brightness changes a little differently on each note, like a gate-fired envelope whose depth wanders at random. That is Chris's "chaotic envelope" built from two Distings.