Virasoro Jazz club and restaurant Guatemala 4328 Palermo
Buenos Aires has always had a smallish but high quality Jazz club scene. Virasoro is one club I was not previously aware of but I can now recommend. The food menu was simple but the food itself was good. Ambience of the club is great. Definitely a "jazz club", but it easily is described as small and it's a bit cramped once all the patrons flock in. The music, at least via the band last night, was superb and the room accoustics were as well.
If you dig quality jazz and want also to get a bite to eat. I recommend Virasoro. However, it might be best to call ahead. I think we were lucky last night by doing a "walk in".
Of course, Notorious and the Thelonious Club are also two other excellent choices.
Zappaman