價格：免費
檔案大小：54.8 MB
版本需求：需要 iOS 9.2 或以上版本。與 iPhone、iPad 及 iPod touch 相容。
支援語言：英語
Practice multi-part songs alone. Control the volume of each part separately, so you can:
* Listen to the song with all the parts
* Listen to just one or two or three parts
* Listen with several parts turned down low, so that the part you’re trying to learn comes through more clearly
* Sing along with the volume turned up on the part you’re trying to learn, making it easier for you to keep on track
* Sing along with the volume turned down on your part, challenging yourself to stay on track even with other parts dominating
* Sing along with the volume turned off on your part — the ultimate challenge
支援平台：iPhone, iPad