audio.xml

<?xml version="1.0" encoding="UTF-8"?>
<Audio version="1.0" timeUnit="ms" interactionArea="#touchArea" gain="-15dB">
    <Chain portamento="200">

        <OscillatorNode type="sawtooth">
            <frequency follow="relX" map="0, 100, 60, 200"></frequency>
        </OscillatorNode>

        <BiquadFilterNode type="lowpass">
            <frequency follow="relX" map="0, 100, 240, 600"></frequency>
            <Q follow="relX" map="0, 100, 0, 1, (x * (600-240) + 240) / 38"></Q>
        </BiquadFilterNode>

        <BiquadFilterNode type="lowpass">
            <frequency follow="relY" map="100, 0, 600, 2000"></frequency>
            <Q follow="relY" map="100, 0, 0, 1, (x * (2000-600) + 600) / 45"></Q>
        </BiquadFilterNode>

        <GainNode>
            <gain>
                <Envelope adsr="200, 100, 100, 100" trig="pointer" max="1"></Envelope>
            </gain>
        </GainNode>

    </Chain>
</Audio>