⚡ ReplicantFX

A CPU-Friendly Cyberpunk SP-404MKII Multi-FX Processor & Retro LED Filter Visualizer
Built in pure Rust using NIH-plug and egui. Clones all 48 MFX slots from the Roland SP-404MKII v5.52 firmware with a NIGHT CITY HUD, Dual-Bus Serial/Parallel routing, dynamic morphing controls, and an interactive Retro Dot-Matrix + 7-Segment LED Filter Screen.

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☕ Support the Project

If you enjoy ReplicantFX and want to support ongoing development, maintenance, and new features:

👉 Support / Buy me a coffee on PayPal (paypal.me/DanimanX)

There is also a direct ☕ DONATE button in the top navigation bar of the plugin itself.

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🌌 Overview

ReplicantFX is a cross-platform Rust audio effect plugin (VST3, CLAP, AUv2, and Standalone) inspired by the ReplicantWave NIGHT CITY HUD design system and engineered from a deep analysis of the SP-404MKII System Firmware v5.52 (SP404MKII_APP1.bin).

It brings the complete 48-slot SP-404MKII MFX catalog (Bypass + 47 active hardware effects), Dual-Bus (BUS 1 & BUS 2) Serial/Parallel routing, 5 instant Direct FX performance pads, a centerpiece Retro Dot-Matrix LED Filter & 7SEG404SX 7-Segment Visualizer, and a Dynamic UI Deck whose rotary knobs and context action buttons morph automatically according to the selected effect.

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🚀 Key Features

📟 Retro Dot-Matrix LED Filter & 7SEG404SX Visualizer

• 56×18 Dot-Matrix LED Screen: Real-time analytical magnitude response curve (H(f) across 20 Hz – 20 kHz) rendered simultaneously as quantized glowing LED dots and a volumetric GPU laser ribbon.
• Authentic 3-Digit 7-Segment Display (7SEG404SX): Top-right hardware LED counter displaying the firmware's 3-character effect code (F+D, 303, 404, ISO, DJL, SCT, JNO, KDM, HDO, etc.) or real-time 000–100 parameter values while dragging.
• 32-Band Spectrum & Live Oscilloscope: Embedded real-time spectrum bars and stereo waveform trace inside the LED bezel.
• Interactive X/Y Filter Pad: Click and drag directly on the Retro LED Screen to sweep CTRL 1 (Cutoff / Frequency / Time) and CTRL 2 (Resonance / Feedback / Peak) simultaneously.

🎛️ Dynamic Morphing Controls & Context Buttons

• 6 Dynamic Rotary Knobs (CTRL 1..3 + SUB 4..6): Automatically relabel and reformat their readouts (Hz, kHz, dB, 100D:0W, musical note/chord names C#2..B5, tempo divisions 1/64..1/1, LP 33 / EP 45 / SP 78, JUNO 1 / 2 / 1+2) to match the exact firmware parameter table of the active effect.
• Dynamic Context Action Strip: Hardware mode and performance buttons below the knobs change per effect:
  • Filter+Drive / Super Filter / Wah: [LPF MODE], [BPF MODE], [HPF MODE], [-12 dB], [-24 dB], [-36 dB], [SUB BOOST], [ACID RESO].
  • Isolator: Instant DJ band-kill switches [KILL LOW], [KILL MID], [KILL HIGH] + flat band resets.
  • DJFX Looper / Stopper / Back Spin: [⚡ LOOP SW], [REVERSE], [🛑 STOP TRIG], and loop length selectors (1/4, 1/8, 1/16, 1/32).
  • 303 VinylSim / 404 VinylSim / Cassette Sim: [LP 33 RPM], [EP 45 RPM], [SP 78 RPM], [DUST CRACKLE], [WARP WOW], [SP-303 COMP], [TAPE CATCH].
  • JUNO Chorus / Phaser / Flanger: [JUNO I], [JUNO II], [JUNO I+II], [JX-1 I], [JX-1 II], [4-STAGE], [8-STAGE], [12-STAGE], [BI-PHASE].
  • Resonator / Hyper-Reso / Vocoder: Chord interval buttons ([ROOT], [FIFTH P5], [MINOR m7], [MAJOR M7], [CYBER m9], [SELF-OSC]).

🔀 Dual-Bus SP-404MKII Architecture (BUS 1 + BUS 2 + MASTER 3/4)

• Dual Independent MFX Engines: Run any two SP-404MKII effects simultaneously on BUS 1 and BUS 2.
• Serial (BUS 1 → BUS 2) or Parallel (BUS 1 ∥ BUS 2) Routing: Matches the firmware's BUSFX_SERIAL and BUSFX_2X2 topologies.
• 5 Hardware Direct FX Buttons: Instant 1-click access to DFX1: Filter+Drive, DFX2: Resonator, DFX3: Sync Delay, DFX4: Isolator, and DFX5: DJFX Looper.
• 🔥 MFX GRAB / HOLD Performance Pad: Momentarily boosts filter resonance and delay/comb feedback for live transitions.
• Built-in Cyberpunk Test Signal Generator: Cycle between EXT IN, CYBER BREAK, ACID 303, NEON PAD, and SUB 808 in the top bar to audition effects immediately in Standalone mode or without an input track.

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🧪 Complete 48-Slot SP-404MKII Firmware MFX Catalog

ID	Effect Name	LED	Category	Firmware Parameters (CTRL 1..3 | SUB 4..6)
00	Bypass	BYP	Direct	GAIN, PAN, LOW TRIM | PHASE, HIGH TRIM, BALANCE
01	Filter+Drive	F+D	Direct FX 1	CUTOFF, RESONANCE, DRIVE | FLT TYPE, LOW FREQ, LOW GAIN
02	TimeCtrlDly	TCD	Delay/Echo	TIME, FEEDBACK, LEVEL | HIGH CUT, LOW DAMP, BALANCE
03	Isolator	ISO	Direct FX 4	LOW, MID, HIGH | KILL LOW, KILL MID, KILL HIGH
04	Crusher	CRS	Lo-Fi/Vinyl	FILTER, RATE, BALANCE | BIT DEPTH, RESONANCE, DRIVE
05	Phaser	PHS	Modulation	RATE, DEPTH, RESONANCE | MANUAL, TYPE, BALANCE
06	Flanger	FLG	Modulation	RATE, DEPTH, RESONANCE | MANUAL, LOW CUT F, BALANCE
07	Overdrive	ODV	Drive/Amp	DRIVE, TONE, BALANCE | LEVEL, AMP TYPE, LOW CUT
08	Distortion	DST	Drive/Amp	DRIVE, TONE, BALANCE | LEVEL, MODE, LOW BOOST
09	Tape Echo	TPE	Delay/Echo	TIME, FEEDBACK, LEVEL | MODE, TAPE DIST, W/F DEPTH
10	Reverb	REV	Reverb	TIME, LEVEL, PRE DELAY | TYPE, LOW CUT, HIGH CUT
11	WrmSaturator	SAT	Drive/Amp	DRIVE, EQ LOW, EQ HIGH | LOW FREQ, HI FREQ, BALANCE
12	Resonator	RES	Direct FX 2	ROOT, BRIGHT, FEEDBACK | CHORD, ENV MOD, PANNING
13	DJFX Looper	DJL	Direct FX 5	LENGTH, SPEED, LOOP SW | REVERSE, TONE, LEVEL
14	Chorus	CHR	Modulation	RATE, DEPTH, BALANCE | EQ LOW, EQ HIGH, LEVEL
15	JUNO Chorus	JNO	Modulation	MODE, NOISE, BALANCE | RATE, DEPTH, LEVEL
16	Tremolo/Pan	TRM	Modulation	RATE, DEPTH, TYPE | WAVE, EQ LOW, EQ HIGH
17	Wah	WAH	Filter/EQ	MANUAL, PEAK, RATE | FLT TYPE, DEPTH, SENS
18	Sync Delay	SYD	Direct FX 3	TIME, FEEDBACK, LEVEL | HIGH CUT, HIGH DAMP, LOW DAMP
19	Equalizer	EQL	Filter/EQ	LOW GAIN, MID GAIN, HIGH GAIN | LOW FREQ, MID FREQ, MID Q
20	Lo-fi	LFI	Lo-Fi/Vinyl	PRE FILT, LOFI TYPE, TONE | CUTOFF, POST FILT, BALANCE
21	Ring Mod	RNG	Modulation	FREQUENCY, SENS, BALANCE | POLARITY, EQ LOW, EQ HIGH
22	Chromatic PS	CPS	Pitch/Voice	PITCH1, PITCH2, BALANCE | FINE1, FINE2, PAN SPREAD
23	Gt Amp Sim	AMP	Drive/Amp	AMP TYPE, DRIVE, LEVEL | BASS, MIDDLE, TREBLE
24	Stopper	STP	Beat/DJFX	RATE, STOP TRIG, DEPTH | FILTER, RESONANCE, LEVEL
25	Downer	DWN	Beat/DJFX	DEPTH, RATE, FILTER | PITCH, RESONANCE, LEVEL
26	Slicer	SLC	Beat/DJFX	PATTERN, SPEED, DEPTH | ATTACK, SHUFFLE, MODE
27	Auto Pitch	ATP	Pitch/Voice	PITCH, FORMANT, BALANCE | AT PITCH, KEY, ROBOT
28	Compressor	CMP	Drive/Amp	SUSTAIN, ATTACK, LEVEL | RATIO, TONE, BALANCE
29	303 BusComp	C02	Drive/Amp	SUSTAIN, ATTACK, LEVEL | RATIO, TONE, BALANCE
30	Scatter	SCT	Beat/DJFX	SCATTER, DEPTH, SPEED | GATE, ATTACK, BALANCE
31	404 VinylSim	404	Lo-Fi/Vinyl	FREQUENCY, NOISE, WOW FLUT | DIST, DISC TYPE, BALANCE
32	303 VinylSim	303	Lo-Fi/Vinyl	COMP, NOISE, WOW FLUT | AGE, TONE, BALANCE
33	Zan-Zou	ZNZ	Delay/Echo	TIME, FEEDBACK, HF DAMP | MODE, SPREAD, LEVEL
34	Super Filter	SFL	Filter/EQ	CUTOFF, RESONANCE, FLT TYPE | FLT SLOPE, RATE, DEPTH
35	Hyper-Reso	HYP	Filter/EQ	NOTE, SPREAD, FEEDBACK | CHARACTER, ENV MOD, LEVEL
36	Ko-Da-Ma	KDM	Delay/Echo	TIME, FEEDBACK, SEND | MODE, HIGH CUT, MOD DEPTH
37	Ha-Dou	HDO	Reverb	TIME, LEVEL, MOD DEPTH | PRE DELAY, LOW CUT, DENSITY
38	To-Gu-Ro	TGR	Modulation	DEPTH, RATE, RESONANCE | FLT MOD, AMP MOD, HOLD
39	Cassette Sim	CAS	Lo-Fi/Vinyl	TONE, HISS, WOW FLUT | AGE, DRIVE, CATCH
40	SBF	SBF	Filter/EQ	INTERVAL, WIDTH, BALANCE | TYPE, GAIN, LOW CUT
41	SX Delay	SXD	Delay/Echo	TIME, FEEDBACK, BALANCE | FBK ROUTE, HF DAMP, MOD DEPTH
42	Vocoder	VOC	Pitch/Voice	NOTE, FORMANT, TONE | CHORD, COLOR, BALANCE
43	Harmony	HRM	Pitch/Voice	PITCH, HARMONY, BALANCE | FORMANT, KEY, AT PITCH
44	SX Reverb	SXR	Reverb	TIME, TONE, BALANCE | TYPE, PRE DELAY, LEVEL
45	Sub Sonic	SUB	Filter/EQ	FREQ, SUB LEVEL, BALANCE | DRIVE, TONE, DIRECT
46	Back Spin	BSP	Beat/DJFX	LENGTH, SPEED, BACK SW | CURVE, TONE, LEVEL
47	Cloud Delay	CLD	Delay/Echo	PITCH, WINDOW, FEEDBACK | CLOUDY, LOFI, BALANCE

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🛠️ Building & Packaging from Source

Prerequisites

• Rust 1.85+ (MSRV)
• Linux audio/window headers (Ubuntu/Debian):

  sudo apt-get install -y libasound2-dev libgl1-mesa-dev libx11-xcb-dev libxcb1-dev libxcb-render0-dev libxcb-shape0-dev libxcb-xfixes0-dev libjack-jackd2-dev
  

Build Everything

# Clone the repository
git clone https://github.com/DanimanX/ReplicantFX.git
cd ReplicantFX

# Run DSP & Filter Response verification test suite
cargo test

# Bundle VST3 & CLAP plugins + build Standalone binary
cargo xtask bundle replicantfx --release
cargo build --release --bin replicantfx-standalone

Compiled bundles are generated in target/bundled/:

• target/bundled/replicantfx.vst3
• target/bundled/replicantfx.clap
• target/release/replicantfx-standalone

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📜 License

ReplicantFX is licensed under the MIT License.
Created with ⚡ by Daniel Rojas (daniel.rojas@chileatiende.cl).