soundManager

soundManager (from scenerystack/tambo) is a singleton — not a class you instantiate — that every tambo sound generator ultimately connects through. It owns the shared AudioContext signal chain (a dynamics compressor limiter, a convolver-based reverb send, per-category gain nodes, and a "ducking" gain stage), and exposes the register/unregister API that individual SoundGenerator instances (like SoundClip and PitchedPopGenerator) use to reach the speakers. A sim must call soundManager.initialize(...) once before any sound generator can be added; until then, addSoundGenerator calls are queued and flushed automatically on initialization.

import { soundManager } from 'scenerystack/tambo';
import { SoundClip } from 'scenerystack/tambo';
import myClick_mp3 from './myClick_mp3.js';

Registering a sound generator

const clickSound = new SoundClip( myClick_mp3, { initialOutputLevel: 0.7 } );

// Connects clickSound into the shared audio graph (reverb + dry paths).
soundManager.addSoundGenerator( clickSound, {
  categoryName: 'user-interface' // one of the categories passed to initialize(), or omit for the default routing
} );

// Later, if the sound generator is disposed:
soundManager.removeSoundGenerator( clickSound );

If soundManager.initialize() hasn't run yet (e.g. sound isn't supported in this sim), addSoundGenerator silently queues the request rather than throwing — it's flushed once initialize() completes.

Key members

Member	Description
enabledProperty	BooleanProperty — master on/off switch for all sound; sound generators go silent (via their own fullyEnabledProperty) when this is false
extraSoundEnabledProperty	BooleanProperty — enables sound generators registered at the "extra" sonification level (see SoundLevelEnum), used for supplementary sounds aimed at learners with visual disabilities
initialized	boolean — becomes true after initialize() runs; sound generators can't be meaningfully added before this
mainOutputLevel / getMainOutputLevel() / setMainOutputLevel(level)	Overall gain (0-1) applied to all registered sound, when enabledProperty is true
reverbLevel / getReverbLevel() / setReverbLevel(level)	Wet/dry mix (0-1) for the shared convolver-based reverb send

Methods

Method	Effect
initialize(simConstructionCompleteProperty, audioEnabledProperty, simVisibleProperty, simActiveProperty, simSettingPhetioStateProperty, options?)	One-time setup: builds the audio graph, wires the gain-shutoff Multilink, and flushes any queued sound generators. options.categories (default ['sim-specific', 'user-interface']) defines the category names available to addSoundGenerator
hasSoundGenerator(soundGenerator)	Returns whether a given sound generator is currently registered
addSoundGenerator(soundGenerator, options?)	Connects the sound generator into the graph — either a named categoryName gain node or the default convolver/dry paths — and adds it to the internal list
removeSoundGenerator(soundGenerator)	Disconnects and removes a previously-added sound generator
setOutputLevelForCategory(categoryName, level) / getOutputLevelForCategory(categoryName)	Per-category gain control, e.g. turning down all 'user-interface' sounds independent of 'sim-specific' ones
addDuckingProperty(property) / removeDuckingProperty(property)	Registers a TReadOnlyProperty<boolean> that, when true, temporarily reduces overall output (used so sound effects duck under Voicing speech)

Sound generators still gate themselves

soundManager.enabledProperty being true doesn't guarantee a given SoundClip or PitchedPopGenerator actually plays — each SoundGenerator computes its own fullyEnabledProperty from soundManager.enabledProperty and its own enabledProperty, sonification level, associated-view-node visibility, and whether the sim is mid-reset or setting PhET-iO state. See How tambo's Sound Generation Fits Together for how these layers compose.