A basic PA (public address) system is what most dance studios need. This includes: a sound source, such as your phone or tablet; a mixer, which will allow you to play multiple sound sources; an amplifier, to strengthen the signal from your sound sources; and speakers, which convert an electrical sound signal into something that your dancers can hear—loudly.
These days, you can find an amp-mixer combination, which is called a powered mixer, as well as an amp-speaker duo, which is called powered speakers. Generally, you use a powered mixer with passive speakers or vice versa. Most sound experts recommend powered speakers with a passive mixer, since you can plug directly into powered speakers for a quick fix. When looking for speakers, find out how well they handle low end/bass sound. That tends to be key for dance classes.
I’m quite happy with my Yamaha STAGEPAS PA system. It has a powered mixer and passive speakers and is more than enough for my studio. Plus, PA systems like this one are built to be portable (and not too heavy): You place the mixer right into one of the speakers, and you can move the system quite easily.
Since your music will be nice and loud, consider adding a microphone component to your system. I have a wireless microphone that helps me preserve my voice as I speak over the music. Shure wireless microphones are the industry standard.
Barry Blumenfeld teaches at the Friends Seminary in New York City. He is an adjunct professor at New York University and on faculty at the Dance Education Laboratory of the 92nd Street Y.
Photo courtesy of Barry Blumenfeld