U = (x) -> @graph.Uri(x)

    effectUri = U(":effect") + "/#{uriName}"

    quad = (s, p, o) => {subject: s, predicate: p, object: o, graph: ctx}

    addQuads = [

    playerSong: {type: String, notify: true}

    followPlayerSong: {type: Boolean, notify: true, value: true}

    song: {type: String, notify: true}

    songTime: {type: Number, notify: true, observer: '_onSongTime'}

    songDuration: {type: Number, notify: true, observer: '_onSongDuration'}

    songPlaying: {type: Boolean, notify: true}