Not exactly, but you can create extra Sound Managers:
new Phaser.Game({
callbacks: {
preBoot: function (game) {
game.music = Phaser.Sound.SoundManagerCreator.create(game);
game.uiSound = Phaser.Sound.SoundManagerCreator.create(game);
// That makes 3 in all (after `game.sound`)
}
}
});