     
     var controlRate: Double = 1 / 60 // 60 times per second
     var curveType: CurveType = .Linear
-    var curvature: Double = 0.5 //doesn't apply to linear
+    var taper: Double = 0.5 //doesn't apply to linear
     var duration: Double = 1.0 //seconds
     var offset: Double = 0.0
     var stepCounter = 0

         finalVolume: Double,
         duration: Double = 1.0,
         type: CurveType = .Exponential,
         curvature: Double = 1.0,
         offset: Double = 0.0,
         output: AKBooster) {
        
        self.initialVolume = initialVolume
        self.finalVolume = finalVolume
        curveType = type
        self.curvature = curvature
        self.duration = duration
        self.offset = offset
        numberOfSteps = Int(floor(duration / controlRate))

            case .Exponential:
                scaledControlAmount = controlAmount.denormalized(minimum: source,
                                                                 maximum: target,
                                                                 taper: taper)
            case .EqualPower:
                //direction will be negative if going up
                scaledControlAmount = pow((0.5 + 0.5 * direction * cos(M_PI * controlAmount)), 0.5)
