orklev2-audio

name	orklev2-audio
description	Answer questions about orkid's Singularity synthesizer engine, DSP processing, oscillators, filters, envelopes, modulation, sampling, FM synthesis, audio output, and program/bank structure. Use when the user asks about audio, synth, DSP, or sound.
user-invocable	false

Orkid Singularity Audio/Synth Engine Reference

When answering questions about audio or the synthesizer in orkid, consult the files below. All under ork.lev2/.

Key Files

Component	Header
Synth Engine	inc/ork/lev2/aud/singularity/synth.h
Layer (Voice)	inc/ork/lev2/aud/singularity/layer.h
DSP Blocks/Pipeline	inc/ork/lev2/aud/singularity/dspblocks.h
Program/Bank Data	inc/ork/lev2/aud/singularity/synthdata.h
Oscillators	inc/ork/lev2/aud/singularity/alg_oscil.h
Filters	inc/ork/lev2/aud/singularity/alg_filters.h
Amplitude/Gain	inc/ork/lev2/aud/singularity/alg_amp.h
Nonlinear/Distortion	inc/ork/lev2/aud/singularity/alg_nonlin.h
Envelopes	inc/ork/lev2/aud/singularity/envelope.h
Controllers/LFO	inc/ork/lev2/aud/singularity/controller.h
Modulation Routing	inc/ork/lev2/aud/singularity/modulation.h
Sampler	inc/ork/lev2/aud/singularity/sampler.h
Wavetable	inc/ork/lev2/aud/singularity/wavetable.h
FM Operators	inc/ork/lev2/aud/singularity/fmosc.h
TX81Z Emulation	inc/ork/lev2/aud/singularity/tx81z.h
CZ1 Phase Distortion	inc/ork/lev2/aud/singularity/cz1.h
Delays	inc/ork/lev2/aud/singularity/delays.h
DSP Buffer	inc/ork/lev2/aud/singularity/dspbuffer.h
Key On/Off	inc/ork/lev2/aud/singularity/konoff.h
Types	inc/ork/lev2/aud/singularity/krztypes.h
Audio Device	inc/ork/lev2/aud/audiodevice.h

Architecture Overview

Execution Model

• Voice-based polyphonic synthesis (up to 512 voices)
• Control rate: 1500 Hz (32 frames @ 48kHz)
• Sample rate: 48 kHz
• Per-voice DSP pipeline with stages in series

Signal Flow

Voice -> Layer -> Algorithm (multi-stage)
  -> DspStage 0 [Block0, Block1, ...] -> DspStage 1 -> ... -> OutputBus
    -> Insert Effects -> Master EQ -> Audio Device

Core Classes

• synth — main engine, voice allocation, output buses
• Layer — runtime voice instance, holds DSP state
• LayerData — voice config (algorithm, controllers, keymap, pitch)
• Alg / AlgData — algorithm container (up to 16 stages)
• DspStage / DspStageData — stack of up to 32 DSP blocks
• DspBlock / DspBlockData — individual DSP unit (abstract base)

Program/Bank Structure

BankData
+-- programs (int -> ProgramData)
+-- keymaps (int -> KeyMapData)
+-- multisamples (int -> MultiSampleData)

ProgramData
+-- name, tags, monophonic, portamento
+-- _layerdatas[] (multiple layers per program)
    +-- LayerData
        +-- _algdata (DSP algorithm)
        +-- _ctrlBlock (controllers)
        +-- _kmpBlock (keymap for samples)
        +-- loKey/hiKey, loVel/hiVel (range)
        +-- output bus routing

Oscillator Types

• SINE, SAW, SQUARE (band-limited with PolyBLEP)
• SINEPLUS, SAWPLUS, SWPLUSSHP (harmonically enriched)
• SHAPEMODOSC, PLUSSHAPEMODOSC (shape modulation)
• SYNCM / SYNCS (oscillator sync master/slave)
• SAMPLER (multi-sample playback with keymaps)
• TX81Z FM operators (4-op Yamaha emulation)
• CZ1 phase distortion

Filter Types

• TrapSVF — state variable (LPF/HPF/BPF/Notch, trap-rule)
• BiQuad — 2nd-order IIR
• OnePoleLoPass / OnePoleHiPass — 1st order
• ParaOne — parametric EQ with shelving
• DSP blocks: LP2RES, LOPAS2, LPGATE, BANDPASS_FILT, NOTCH_FILT, etc.

Envelope Types

• RateLevelEnvData — ADSR-style with segment times/levels
• AsrData — Attack-Sustain-Release
• YmEnvData — Yamaha: AR/D1/S/D2
• TX81ZEnvData — TX81Z with polynomial rate scaling

Modulation System

DspParamData
+-- _coarse (base value)
+-- _fine (fine tuning)
+-- _keyTrack (keyboard follow)
+-- _velTrack (velocity follow)
+-- _mods (BlockModulationData)
    +-- _src1 (primary: LFO, envelope, etc.)
    +-- _src2 (depth modulation)

Custom evaluators: pitch, frequency, amplitude, or lambda-based.

Key On/Off

synth::keyOn(note, vel, program, keyonmods)
  -> Layer::keyOn(note, vel, layerdata, outputbus)
    -> Alg::keyOn() -> all DspBlocks, Controllers

How to Answer

1. For DSP blocks: check dspblocks.h for base class, alg_*.h for specific types
2. For modulation: read modulation.h for routing, controller.h for LFO/envelope sources
3. For sample playback: read sampler.h for KeyMapData, MultiSampleData, SampleOscillator
4. For program structure: read synthdata.h for BankData/ProgramData hierarchy