2026/06/04 4:41
Brume is a 24-voice multi-timbral desktop synth for the CM5
RSS: https://news.ycombinator.com/rss
要約▶
本文
● Aftertone & Signal / Instrument № 01
Open-source software that turns a Raspberry Pi Compute Module 5 and a touchscreen into a standalone four-part synthesizer — four engines, one filter, and one cable to your DAW. 01 / Engines Four voices, four lineages. Brume runs four synthesis engines with a shared voice tail (state-variable filter, amp envelope, modulation router), so patches stay coherent across very different sources. Each engine has its own mechanism for continuous spectral change: algorithm routing and per-voice FM-index envelopes in FM, a scanning window in Harmonic, cascaded wavefolding in Timbral, grain scatter in Granular. No samples sit anywhere in the signal path; every voice is generated from live math. ◆ Part 1 · FM FM Metallic overtones from stacked sines Six operators across twelve algorithm topologies, per-op ratio and level, global feedback, a per-voice FM-index envelope, and a voice-tail state-variable filter with its own envelope — DX-style FM with subtractive shaping on the way out. 6 5 4 3 2 1 ALG 1 · STACK 6-OP12 ALGOSFDBKINDEX ENVFILTER ◆ Part 2 · Harmonic Harmonic Additive synthesis under a scanning window Eight harmonics with Gaussian scanning, per-harmonic waveform morph, FM on the fundamental, spectral tilt, and odd/even balance. SCANMORPHTILTODD/EVNSPREAD ◆ Part 3 · Timbral Timbral Triangle core folded into nonlinear spectra Triangle core through a wave-multiplier shaper with linear FM, sub-oscillator, self-modulation feedback, and expanded symmetry. TIMBRESYMMETRYMULTIPLYLIN FMSUB ◆ Part 4 · Granular Granular Pitched grain clouds that drift and scatter Pitched clouds of micro-oscillator grains with morphable waveforms. Density, scatter, drift, and FM within grains. DENSITYSCATTERDRIFTMORPHFM 02 / Signal architecture Every voice, the same path. MIDI in, voice allocation, modulation, filter, envelope, mixer. Sends to delay and reverb. A Lua FX slot for custom processing. MIDI IN CHANNEL MAP FM HARMONIC TIMBRAL GRANULAR MOD MATRIX LFO · ENV · VEL FILTER MIXER LEVEL · PAN · MUTE SEND BUSES SATURATOR CHORUS DELAY REVERB LUA FX SCRIPT FX + MASTER LIMITER · STEREO AUDIO OUT 03 / Meridian One cable to your DAW. One USB cable carries multi-channel audio out, bidirectional MIDI, and clock. Class-compliant — no drivers, no manager app. Source Brume 4 engines · 24 voices · dry + sends rendered per part. Link · USB Audio · MIDI · Clock Class-compliant. One port. Stereo out plus planned per-part stems. Destination Your DAW Bitwig, Logic, Ableton, Reaper. Arm a track, point at Brume, record. BRUME DAW USB · CLASS COMPLIANT · AUDIO + MIDI + CLOCK macOS · Linux 04 / Specification Purpose-built on Compute Module 5. Raspberry Pi OS Lite, Rust audio runtime, 10.1-inch capacitive touch. Boots fast. Bridges to your DAW over USB. EnginesFM · Harmonic · Timbral · Granular Polyphony24 voices · 6 per part FilterSVF per voice, 2 ADSR per voice Modulation2 LFO + 2 step seq per part EffectsSaturator · Chorus · Delay · Reverb SendsPer-part delay + reverb sends MIDIUSB class-compliant, clock sync MeridianUSB to DAW — audio + MIDI + clock Display10.1″ 1024×600 capacitive touch ScriptingLua 5.4 — sequencing, DSP, custom FX PlatformRust runtime, RT Linux, CM5 ARM A76 05 / Bill of materials Four components. One cable. Boot and play. The hardware is a deliberate assembly of off-the-shelf parts — the instrument is the software. 01 · Compute Module 5 BCM 2712 8GB eMMC WiFi COMPUTE MODULE 5 CM5 Compute Module 5. Quad-core ARM A76, 8 GB RAM, 32 GB eMMC, wireless. 02 · Carrier board CM5 SOCKET GPIO USB-C HDMI USB-A ETH J2/OTG IO BOARD Carrier Board CM5 IO Board with USB OTG for multi-channel audio and MIDI to your DAW. HDMI, GPIO, Ethernet. 03 · Display HDMI+USB 10.1″ TOUCHSCREEN Touchscreen Pick the HDMI touchscreen that fits your build. Brume’s UI is designed around a 1024×600 logical layout and auto-scales to whatever panel you connect — tap into the CM5 touchscreen ecosystem. Reference unit: 10.1″ 1920×1200. 04 · Software BRUME labwc + webkitgtk AUDIO CONFIG PI OS LITE eMMC / 32 GB LINUX INSTALL Software Brume installs onto Raspberry Pi OS Lite. The brumectl CLI adds the runtime packages, labwc/webkitgtk shell, audio config, presets, and systemd service; --update refreshes the binary and factory presets over SSH. Controllers 05 · Reference controller nanoKONTROL2 KORG 1 2 3 4 5 6 7 8 NANOKONTROL2 Controller Korg nanoKONTROL2 is the reference USB-MIDI controller — 8 knobs, 8 faders, transport, and per-strip S/M/R. Brume ships with a default CC-mapping JSON plus a Lua starter script. 06 · Deep-control surface LaunchControl XL 1 2 3 4 5 6 7 8 LAUNCH CONTROL XL 3 Deep surface Novation Launch Control XL 3 positions as the deeper control option — 24 endless encoders, 8 faders, 16 pads, transport. In development as a first-class surface: dedicated CC-mapping JSON with a per-engine page layout, Lua starter scripts. 07 · Open control layer Extend Plug in a class-compliant MIDI controller, touch MIDI learn, save the mapping, then shape the behavior in Lua. Map a controller you like, then share the mapping and a starter script so everyone gets it out of the box. 01MIDI learn 02Lua behavior 03Contribute support