If you want to round over the edges of your speaker cabinet then the best way to do it is with a router.

In this video I show how to use a router fitted with 12.5mm round over bit. The test speaker is the Trohet kit found on my website - link provided below.

TROHET KIT - https://www.thespeakerproject.com/tro...

Trim router - https://www.makita.com.au/building-co...

12.5mm rounder over cutter- https://www.carbatec.com.au/round-ove...