Does the questioner want to ask "What is the difference between Pioneer Audio 939 and 959"? Different functions, different appearances, and different positioning.

1. According to the official website of Pioneer Electronics, the functions are different: Pioneer Audio 939 is a home theater receiver that supports surround sound in Dolby Atmos and other formats. The 959 is a vertical speaker suitable for use as part of a home music system.

2. Different appearance: Pioneer Audio 939 adopts a traditional flat-panel shape, with a front panel display screen and physical button control; while 959 is a column-type speaker with a more fashionable and simple appearance.

3. Different positioning: Pioneer Audio 939 is positioned in the high-end market, with more powerful power and more functions; while 959 is a mid-range product suitable for ordinary home users.