I have no idea bout about other browsers, but in Google chrome
when a sound "happens" a small speaker icon appears within the sound making tab.
When you enter the arena and you hear the gong the speaker icon appears.
So why would the longer gong be useful?
Well, not the gong,
but the sound itself.(standard ~3 seconds of *GOOONG*+2-7 seconds of silence)
As what I'm trying to say is that if the sound was to last ~5-10 seconds, rather than 3, when you are doing something else on some other tab, and you don't hear the gong (due to too loud music, volume being too low, etc.), you will have more time to see that you entered the arena.As in the current state if you miss both the sound AND the icon you are doomed unless you check the nod tab in time.
Because if you don't check the nod tab every ~30 seconds then you are gonna have a bad time.(death due to afkness)
Longer the "speaker icon" stays, the more time you have to notice the arena (speaker icon).
Picture:
