Concert Garb 
Choose something black with formal elegance.

Men- Tux or Black Suit, Black shoes, colored accents acceptable.
Ladies- long black dress, pants or skirt 
Velvet, satin, sparkles, colored accents acceptable.   
    
Thrift stores are a great source of formal wear. You probably have a friend or two who could be on the lookout for something fabulous. Amazon also has inexpensive and pretty comfortable formal pieces.

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