public void setProperties(EffectiveAppearance app) {
   super.setProperties(app);
   FDNParameters params =
       (FDNParameters)
           app.getAttribute(
               AudioAttributes.FDN_PARAMETER_KEY,
               AudioAttributes.DEFAULT_FDN_PARAMETERS,
               FDNParameters.class);
   if (params != parameters) {
     setParameters(params);
   }
   float reverbTime =
       app.getAttribute(AudioAttributes.REVERB_TIME_KEY, AudioAttributes.DEFAULT_REVERB_TIME);
   if (reverbTime != params.getReverbTime()) {
     params.setReverbTime(reverbTime);
   }
 }
 public void clear() {
   super.clear();
   for (float[] line : delayLines) {
     Arrays.fill(line, 0);
   }
 }