reduce dynamicImpactFactor to 0.6 so that a piano dynamic isn't almost inaudible

src/Playback/PlaybackManager.ts

@@ -98,7 +98,7 @@ export class PlaybackManager implements IPlaybackParametersListener {
     private currentReferenceBPM: number;
     private readonly defaultVolume: number = 0.8;
     private currentVolume: number = this.defaultVolume;
-    private dynamicImpactFactor: number = 1.0;
+    private dynamicImpactFactor: number = 0.6;
     private scorePositionChangedData: CursorPosChangedData = new CursorPosChangedData();
     private tooManyInstruments: boolean = false;