The Shure 819 is a unique condenser microphone in the form of a PZM (pressure zone microphone) aka boundary mic. The mic has a uni directional polar pick up pattern and has a standard XLR connection. The mic can be used in just about any situation whether it be in the recording studio, for a live show, or for recording a conference or something of that nature. However, I've only used the mic for recording in the studio so this review will focus on this application of the 819.
Overall, the Shure 819 is a very good sounding microphone. It isn't the most versatile mic in the world, but if you are looking for a boundary mic then you know what its best applications are and how it might be useful to you and the sound that you are going for. I like using this mic in a variety of situations, but will mostly use it to get a general room sound. It is great for an easy recording of a live session in the studio and I would imagine that this trait would transfer well if you wanted to take it into the field and record a live show. I have also gotten good results with the mic for recording the inside of a kick drum as well as for getting an extra signal for electric guitar. In all of the situations however, I did use the 819 in tandem with another microphone as I'm not sure that I could get the sounds that I was after with only using this mic. I find that when I have two microphone to work with the blend the sound of the 819 with another mic, that I'm much happier than I would be with on the 819. These aren't easy mics to find as they are no longer made, and I've seen there is a big difference in mic's price range. However, if you're looking for a PZM mic that sounds great for what it does, I would definitely recommend checking out the Shure 819 as it is just as good as any in its price range.