selection_start = new AudioClock ("selection-start", false, "selection", false, false, false, false);
selection_end = new AudioClock ("selection-end", false, "selection", false, false, false, false);
selection_length = new AudioClock ("selection-length", false, "selection", false, false, true, false);
selection_start = new AudioClock ("selection-start", false, "selection", false, false, false, false);
selection_end = new AudioClock ("selection-end", false, "selection", false, false, false, false);
selection_length = new AudioClock ("selection-length", false, "selection", false, false, true, false);