The U 87 Ai switchable microphone is the successor model to the U 87 i, probably the best known and most widely used microphone in the fet 80 series. The changes affect the increased output voltage and the reduced equivalent noise level. Both measures contribute to a remarkable improvement in recording quality. The microphone is used as the main microphone in studios for orchestral recordings and as a spot microphone for individual instruments. The U 87 Ai and its many features are used for broadcasting big bands and for recording instrumental and vocal soloists, as well as for such difficult tasks as producing a radio play.
Three switches on the capsule head can be used to set the three directional characteristics omnidirectional, cardioid and bi-directional, a low-frequency roll-off and a 10 dB pre-attenuation.