Hanoi Opera, Hanoi
Classic music or jazz events sponsored by embassies and companies are great at Hanoi. Almost all foreigners living in Hanoi will join these events, because they are rare (at least compared to big cities where you have more Nightlife).
Sometimes oyu will get the chance to listen to famous musicians for around 10 USD in a very private armosphere..
Dress Code: Dress up if you can!