This might seem crazy but, clocking in at 99.2 Decibels, the Water Boatman insect has a penis noise that is louder than a freight train when adjusted for size.

Here is the article:  https://io9.gizmodo.com/the-water-boatmans-singing-penis-makes-it-the-loudest-a-5817623?utm_medium=sharefromsite&utm_source=_facebook&fbclid=IwAR2KWqiuF1awYQUgEQo6y-Zj2Z8EeQ3Ae5plz0CSo7qOR5bb1k1ccR6JSc4