So it's +15% then?
You can see that it's not adding 15 seconds to lullaby. While we would predict +9 seconds added to a 60 second base song, we observe +8 seconds. It could be that it's actually only +14%, or it could be that something else is causing the disparity. Point is, it's a percentage boost rather than a static one.
Yeah, percent of the base song duration. Isn't that how all brd gear works?
Base: 60
Kali +5% 3sec
Gjallarhorn +40% 24sec
Matinee +10% 6sec
Hongreline +10% 6sec
Inyanga +15% 9sec
Brioso +11% 6.6sec...?
+14secs JP
Total:128.6 secs or 2:08
As for the slight time variance, I'd say it's probably due to timestamps being a bit off or Brioso's .6 screwing things up.