Single type, two nodes, closures

main.js

var context = new AudioContext();
var audioWorker = context.createAudioWorker("worker.js");
var sine1 = context.createAudioWorkerNode(audioWorker, {
    numberOfInputChannels: 0,
    numberOfOutputChannels: 1,
    parameters: {
        frequency: 440,
    },
});
var sine2 = context.createAudioWorkerNode(audioWorker, {
    numberOfInputChannels: 0,
    numberOfOutputChannels: 1,
    parameters: {
        frequency: 440,
    },
});

sine1.connect(context.destination);
sine2.connect(context.destination);

worker.js

self.addEventListener("onaudionodecreated", function createSine (event) {
    var clock = 0;

    event.node.onaudioprocess = function processBlock (event) {
        let blockSize = event.parameters.frequency.length;

        for ( let output of event.outputBuffers ) {
            for ( let i = 0; i < blockSize; i++ ) {
                let phase = (clock + i) * event.parameters.frequency[i] / event.sampleRate;
                output[i] = Math.sin(Math.PI * phase);
            }
        }

        clock += blockSize;
    };
});