Valis

Valis is a DAW plugin that builds virtual-analog circuits from RDF/Turtle descriptions. The circuit is not compiled into the plugin: it is a document you can read, edit and hand to a language model.

Releases

Video Demo

• Writing circuits : the Turtle format, elements and arcs
• Element reference : every class the ontology declares
• Console : the REPL tab and the AI circuit designer
• The MCP surface : driving the plugin over HTTP
• Building : prerequisites and the build
• Guide for agents : how to build instruments and processors via MCP

Case studies

• SH-101 subtractive synth : monophonic VCO → VCF → VCA with MIDI and LFO
• Klon Centaur : asymmetric diode overdrive with clean blend
• Mutable Instruments Rings : Karplus-Strong plucked string, and how to create a new element
• TR-909 drum synthesiser : per-note drum routing, bridged-T resonators, and sectioned controls

See Also

• Downspout : VST3 plugins
• Transmission : Generative Audio Workstation
• Flues : earlier LV2 plugins and Web Audio toys
• danny.ayers.name : blog

Why RDF

An audio plugin normally hides its structure. Its topology is compiled in, its parameters are whatever the author decided to expose, and a preset is a list of numbers against a fixed graph.

Valis inverts that. The circuit is a graph in a standard format, described with a published vocabulary that reuses LV2's own terms for ports, ranges and units. That makes three things possible that a bespoke plugin cannot do:

• A preset can change the topology, not just the values. Two presets can route the signal differently, or use different devices entirely.
• The structure is inspectable. The graph view draws the actual signal flow because it reads the same document the engine runs.
• A language model can design the sound, because every operation the interface can perform is reachable over HTTP MCP against a described vocabulary.

A circuit

@prefix val: <http://purl.org/stuff/valis/> .
@prefix :    <urn:valis:basic#> .

:basic a val:Circuit ;
    val:element :in , :vcf , :drive , :out ;
    val:arc :a1 , :a2 , :a3 .

:in    a val:Input .
:vcf   a val:Ladder ; val:cutoff 800.0 ; val:resonance 0.4 .
:drive a val:DiodePair ; val:seriesResistance 2200.0 .
:out   a val:Output .

:a1 a val:Arc ; val:from [ val:node :in    ; val:port "out" ] ;
                val:to   [ val:node :vcf   ; val:port "in"  ] .

The proof of concept is Skream: the Massive "scream" filter, expressed as a circuit rather than as ported DSP.