Wether you like country, salsa, hip hop, or just having a drink with friends and listening to live music, then you will find a place just right for you! Here are some of the places I enjoyed and hope you do as well:
Ocho Segundos (Mexican country and "banda" music)-CLUB
El Grito (Hip Hop and trendy music)-CLUB
Inovvo-(Mixed type of dance music)-CLUB
La escalera- ( little bar at the top of a LONG staircase with many little private rooms)-BAR
Merenderos San Pancho- ( cool bar with good music)
Merenderos San Marcos- (same as above only bigger)
Plaza Crystal Bar- (Karaoke Bar)
Republica Bar- (a more "upscale" bar and lounge)
*This is not including all of the delicious and fun restaurants in the area! Have fun!
Dress Code: Most clubs are casual unless you get into the areas like LOS BOSQUES, etc then probably no jeans and no tennis shoes. That's pretty much it.
While you're in Aguascalientes be sure to see if you can attend one of the dance performances. There are several venues around town so just ask someone at your hotel or at the local Tourism office.
You'll be pleasantly surprised to find out how incredibly professional the performers are and the cost is [usually] very inexpensive.
Dress Code: Mexicans tend to dress much more formally than most but in Aguascalientes it's also common to wear blue jeans and cowboy garb.