The Audio-Technica AT4040 is a large-diaphragm, cardioid capacitor microphone designed for use in the most demanding recording applications. Intended for vocal and general instrument recording (piano, guitars, string instruments, etc.), the microphone's cardioid polar pattern minimizes off-axis signal, reducing ambient and residual noise, and delivers pristine low-noise recordings. The AT4040 has an integral 80 Hz hi-pass filter which provides easy switching from a flat frequency response to a low-end roll-off. The high-pass position reduces the microphone's sensitivity to popping in close vocal use. It also reduces the pickup of low-frequency ambient noise (such as traffic, air-handling systems, etc.), room reverberation, and mechanically-coupled vibrations.