Acid Rack

An acid rack that treats the six classic 303 controls as macros and does accent and slide the way the hardware does: accent comes from velocity (above 100 the filter envelope gets more depth and the VCA jumps), slide comes from overlapping notes with Legato on. Two synth chains cover the two ways Live can fake a 303: Analog for the squelchy 24 dB resonance and Drift for the MS2 12 dB rubbery version. A third chain is an External Instrument pointing at a TD-3 so the same macros and the same distortion/delay chain sit over the hardware. Use it for acid techno, acid house, psytrance offshoots, electro and the occasional trip-hop bassline.

Layout

How it's built

1. New MIDI track, empty Instrument Rack. Two chains first; the hardware chain comes last.
2. Chain "Analog 303": Analog. Osc 1 Saw, level 0 dB; Osc 2 off; noise off. Voice mode Mono, Legato on, Glide on with time 60 ms (legato glide: it only slides when notes overlap). Quick Routing: Osc 1 → Filter 1 only. Filter 1: LP 24 dB, cutoff 600 Hz, resonance 55%. Env 1 → Filter 1 amount 50%. Env 1: A 0 / D 300 ms / S 0 / R 100 ms. Amp 1 env: A 1 ms / D 400 ms / S 0.6 / R 60 ms. In the filter section set velocity → Env 1 amount 0 (the Accent macro raises it). Key tracking 30% so high notes open slightly.
3. After Analog: Overdrive at 1.2 kHz, Q 1.0, Drive 30%, Tone 45%, dry/wet 60% so the band-pass crunch rides on a clean core. Then EQ Eight HP 60 Hz 24 dB.
4. Chain "Drift 303": Drift. Osc 1 Saw (try Rectangle for the square-wave 303), Osc 2 off, noise 0. Voice mode Mono, Legato on, Glide 45 ms. Filter MS2, LP 12 dB, 500 Hz, resonance 60%, Env 2 → filter 45%, Env 2 A 0 / D 300 ms / S 0 / R 80 ms. Amp env A 1 ms / D 350 ms / S 0.5 / R 60 ms. In the mod matrix: Velocity → Env 2 amount, 0% (Accent macro). Drift amount 10% for a little analogue instability.
5. After Drift: Roar in Single routing, shaper Diode, Drive 8 dB, Tone 40%, pre-filter LP at 6 kHz, dry/wet 100%. Then EQ Eight HP 60 Hz.
6. Set both chains’ chain-select zones: Analog 0–63, Drift 64–127. No overlap: this is a switch between two 303 flavours, not a crossfade, so you never get two mono synths fighting over the same pitch.
7. Chain "TD-3": add a chain with External Instrument. MIDI To: your interface’s MIDI out, channel 1 (the TD-3 default). Audio From: the input pair the TD-3 is plugged into. Set hardware latency with the Ping method once (typically 2–6 ms) and store it. Follow with Roar Single Soft Sine 6 dB and EQ Eight HP 60 Hz.
8. TD-3 chain-select zone 110–127, so that above 110 the hardware stacks on the Drift chain. If you want it solo, set the Drift chain to 64–109.
9. Macros only map to Live devices, so the TD-3’s own cutoff/resonance are not reachable from Cutoff/Reso. Send MIDI CC from the clip instead (TD-3 responds to CC 74 cutoff, CC 71 resonance, CC 75 env mod, CC 76 decay, CC 77 accent via its MIDI implementation) or use Expression Control’s modulation outputs to CC. The Dist macro does work on the TD-3 because Roar is inside Live.
10. Macro Cutoff: Analog Filter 1 freq 150 Hz → 5 kHz and Drift filter freq 120 Hz → 5 kHz. Mapped ranges are exponential in Live for frequency parameters, so the knob feels right across the sweep.
11. Macro Reso: Analog Filter 1 res 20–95%, Drift res 20–100%. Drift’s MS2 self-oscillates near the top, which is the point.
12. Macro Env Mod: Analog Env 1 → Filter 1 10–100%, Drift Env 2 → filter 10–100%.
13. Macro Decay: Analog Env 1 decay 80–1200 ms, Drift Env 2 decay 80–1200 ms. On the hardware, accented notes ignore Decay; emulate that by keeping the amp decay fixed and only mapping the filter envelope decay.
14. Macro Accent: Analog velocity → Env 1 amount 0–80%, Drift velocity → Env 2 amount 0–80%, Overdrive drive 20–45% on the Analog chain. Now notes above velocity 100 open the filter further and distort harder, which is the 303 accent in two parameters.
15. Macro Dist: Roar drive 0–24 dB on both Drift and TD-3 chains, Overdrive dry/wet 20–100%, Roar Tone 30–70%.
16. Group the rack with an Echo (Cmd+G): Echo Sync, 1/8 dotted both sides, feedback 35%, Filter HP 200 Hz / LP 5 kHz, Duck off, dry/wet 25%. Expose the inner six macros on the outer rack and add a seventh "Echo" macro (dry/wet 0–50%) if you have the encoder space.
17. Pattern programming: in the MIDI clip, accents are notes at velocity 110–127; slides are notes that overlap the next note by a 32nd. Live 12’s Velocity Shaper transformer can stamp accents on every third 16th; Glissando is not needed, overlap does the slide.
18. Macro Variations: "Deep" (Cutoff 20, Reso 50, Env Mod 40, Decay 30, Accent 60, Dist 10), "Squelch" (Cutoff 45, Reso 85, Env Mod 80, Decay 50, Accent 90, Dist 30), "Burn" (Cutoff 70, Reso 70, Env Mod 60, Decay 40, Accent 100, Dist 100). Exclude Dist from randomization so a random hit does not blow the PA; randomize the other five freely, it is a good acid-line generator.

Macro map

Signal flow notes

Analog 303 chain

Accent on the hardware is a single switch per step that raises the envelope depth and the VCA level and shortens the decay of the accent envelope. Velocity → filter env amount plus Overdrive drive gets you about 80% of the way; the remaining 20% is the characteristic "wow" from the accent sweep circuit, which you can fake with a Velocity → LFO amount mapping (LFO 1 triangle at 6 Hz, one-shot-ish via low amount) if you want it.

Drift 303 chain

TD-3 chain

Variations

• Acid techno: Dist default 70, Roar routing Serial with stage 2 Hard, add Roar’s own Feedback section at 15% for the metallic edge, Echo feedback 55%. See deep techno and industrial techno.
• Acid house: Dist 0–20, Reso 70, Decay 25, Echo at 1/4 dotted with 20% wet, Analog chain only. See minimal house.
• Electro: Drift Osc 1 Rectangle, Glide 20 ms, no Echo, add Pedal (Fuzz, 30%) instead of Roar. See electro.
• Trip-hop bassline: Cutoff 15, Reso 40, Env Mod 30, Accent 50, Dist 10, release up to 150 ms, Echo replaced with Vinyl Distortion. See trip-hop.
• Psytrance acid: Cutoff automation over 16 bars from 20 to 100, Reso 80, Roar Multiband routing with only the high band driven, no Echo but a Delay at 3/16 ping-pong. See psytrance.

Performance notes

• Push: Cutoff, Reso, Env Mod, Decay on encoders 1–4 in that order, mirroring the TD-3 panel; Accent and Dist on 5–6. Macro Variations on the variation buttons give you three acid lines without touching the clip.
• Automation vs macro: Cutoff is the one parameter that should always be played, not drawn. Record the macro moves as automation in Arrangement afterwards if you need them repeatable.
• Hardware: when the TD-3 chain is active, keep the track’s monitoring on Auto and hardware latency compensated; freezing the track is not possible with External Instrument active, so bounce (12.2 Bounce in Place) the hardware take before arranging.
• CPU: trivial. Analog and Drift mono with one oscillator each and one Roar instance.
• Live sets: this rack plus a Beat Repeat after the Echo is a complete acid section. Map Beat Repeat’s Chance to a Push pad.

Related

• Acid 303 · Leads
• Analog and Drift · Roar and saturation · Hardware and modular integration
• Saturation and distortion · Sidechain and ducking
• Lead rack · Modular hybrid rack
• Deep techno · Electro