There is one small local disco in Las Terrenas town, don't remember the name, but you can not miss it as it's not far form the cemetery.... (as an old song from the Spanish group Mecano said.... "No es serio este cementerio"!!! :-)) Just wander around the town centre and follow the music!!
This particular night there was an exhibition of videos from the famous Dominican singer, Anthony Santos. So, lots of their fans there, watching the videos and singing the songs while dancing, wow! locals do dance really well!!... and a few tourists just people-watching and having fun with our sloppy dancing attempts :-)
Later we found that in the central "plaza comercial" of the town, there were local music players and people dancing as well. These Dominicans do know how to have a good time!
The animation group of the former El Portillo resort had some cool night shows. They usually announced the "theme" for the night already in the morning so you could have the choice of skipping it if it wasn't of your liking. The one I liked the most was their Michael Jackson show (my idol #1 as a musician, I don't care what he does as a person).
Dress Code: Come as you are.
Nice small place, in front of the sea, where to have a rest, before having dinner in one of the restaurants (a few in a row in the same beach), or later.... Nice nu-jazz and lounge music (pity the horrendous music from one of the nearby restaurants interfered a bit on this), cool atmosphere, not the cheapest place in town but it deserves a try, affordable in any case.