 
     var currentNoteName: String {
         switch (oneButton.active, twoButton.active, threeButton.active, sharpButton.active, flatButton.active) {
+
         // Natural
         case (false, false, false, false, false), (false, false, false, true, true): return ""
         case (true, false, false, false, false), (true, false, false, true, true): return "C"

                fatalError("unexpected note code: \(noteCode)")
            }
            synthNode.frequency = note.rawValue + vibratoMultiplier*vibrato
            updateShownNote()
            if !synthNode.playing {
                synthNode.startPlaying()
            }
        } else if synthNode.playing {
            synthNode.stopPlaying()
        }
    }

    func buttonTapped(node: ButtonNode) {
        if node.active {
            updateShownNote()
        } else {
            noteLabelNode.text = ""
        }

        triggerUpdate()
    }


        return noteCode
    }

    override func update(currentTime: NSTimeInterval) {
        if pendingUpdate && abs(eventDate.timeIntervalSinceNow) > updateDelay {
            completePendingUpdate()
