use of "versus"

[TerryWang]

Hello:

"Game: Approximately 3 - 6 hours. *1
Video Playback: Approximately 3 - 5 hours. *2

*1 Game figures are "based on tests conducted in single player mode, headphones with remote control in use, wireless LAN not in use".
*2 Video playback figures are "based on tests conducted using variables of system speakers versus headphones, volume level and screen brightness level."

Above is a test result found in a manual. What I found confusing is the use of "versus" in the *2 sentence. If the tests use system speakers versus headphones, does the test result (Video Playback) also include the use of headphones, or exclude headphones simply as a target of comparison?

Thanks very much

 

[Anglika]

It is comparing the headphones to the speakers, judging the performance via headphones against performance via speakers.