This man [Dan Neubecker] is simply amazing. I think he's an architect by profession and he has built some amazingly beautiful speakers. More amazing than the BaSSlines are his Hybrid Omnidirectional Speaker System [a.k.a. HOSS]. It's a work of art. Check out these [and his other builds] here. His builds have won lots of awards too.
all those tools are available in Kannur - that is a mechanically depressed router - and most mechanised wood-working shops have these- you set the depth and the grooves are cut.