This is for the build plans to build your own pair of Dinas Passive. Dinas is short for Do I Need a Subwoofer. And that is because each speaker has it’s own  subwoofer paired with a passive radiator that goes down to an impressive 32hz. These are the passive version of the speakers you saw 123Toid from YouTube build and JoeNTell Review. These speakers are completely passive allowing you to utilize your favorite amplifier with them.