Reservations are a good idea. Dinner only and some morning shows with coffee and pastry. Some dress to the nines some business casual. Very good food and the music is terrific.
Unless its a ticketed event, you should be able to just show up and eat and enjoy any live music going on. Check their calendar for live music. There may be a cover on that side of the venue (other side is bar, food, tv showing the stage). Dress code is fairly relaxed. Some wear suits during a nice concert, but also slacks and even jeans. I wouldnt want to wear a t-shirt but otherwise I wouldn't be too concerned.
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