Dancing in the D.R.

Does anyone have tips on where to go dancing and/or hear live music in the Dominican Republic? This query has come in from a reader:

"We want our four days there to be very much centered around dancing and music. We're hoping to dance with the locals and experience the roots of merengue and bachata firsthand!"

Please share in the comments section!

Updates...

Ok, Salsonero suggests the "only disco grotto in the world"--with a website: Guácara Taína in Santo Domingo.

OC pal Steve seconds that recommendation ("how can you resist saying you danced in a cave?"), and adds two more:

1) La Sartén
Hostos 153
Santo Domingo
"Tiny hole in the wall salsa/merengue club where you can see mostly middle aged and up folks dancing old school. It's like going back in time 30 years. Bring hearing protection, it's loud, even out on the sidewalk, where a large part of the dancing takes place. When I was there, this place was strictly for locals, but I heard a rumor a while back that somebody was taking tourists there. Hard to imagine, but times change. This is in the old center (Zona Colonial)."

2) Kantabar Plaza Unicentro
Av. 27 de Febrero esq. Abraham Lincoln, Unicentro Plaza, Santo Domingo, Republica Dominicana
809-565-1484
"This is actually a Karaoke place, something that I'm typically not really into. Got dragged there, I thought I'd hate it, but ended up loving it. You can see ordinary folks letting their hair down and going through the classics. Looking on the web, it looks like they may have at least 2 locations now, so I hope this is the right one. Lots of dancing going on."