public void setVolume(float volume) {
        if (volume < 0 || volume > 1)
            throw new IllegalArgumentException("Volume must be between 0 and 1");

        this.volume = volume;
        this.updateNeeded = true;
    }
Sets the overall volume.

@param volume the new overall volume scaling (0.0 - 1.0).
@throws IllegalArgumentException if {@code volume} is out of range.
jme3-core/src/main/java/com/jme3/audio/LowPassFilter.java