Microphone placement is a very important part of recording the human voice. Unless you are trying to achieve a special effect, microphones should be paced between 4" and 12" away from the singer and just a little above their mouth to reduce unwanted mouth noises. A pop filter - a mountable mesh screen designed to block unwanted noise from air leaving the mouth - should be placed two to three inches in front of the microphone.
Large diaphragm condenser microphones are usually the first choice of most engineers because they are capable of picking up many of the small details in the human voice. Artists like Frank Sinatra, Paul McCartney and James Taylor have recorded most of their vocal tracks using large diaphragm condenser microphones. Large diaphragm condenser microphones are very sensitive, however, and may not be appropriate for vocalists who are extremely loud or where parts of the song are yelled as in some heavy metal and punk music because of possible distortion.
Dynamic microphones are sometimes used in the recording studio for very loud singers because they are capable of accepting a very high decibel level without distorting the sound. Dynamic microphones generally do not have the same frequency range as other types of microphones and often do not pick up all of the nuances and details produced by the human voice. However, good results can be achieved with dynamic microphones. Bono of U2 recorded many of his most well-known early vocal tracks with a Shure SM-58, a dynamic microphone that costs less than $100. Dynamic microphones are often used for backing vocals because their lack of detail allows them to easily blend into a recorded track.
Ribbon microphones are used to record many singers who perform at a soft volume. Bass singers often use ribbon microphones, as the ribbon element tends to pick up more bass frequencies than high frequencies. Elvis Presley, Billie Holliday and Count Basie recorded many of their most famous vocal tracks using ribbon microphones. Ribbon microphones are sometimes said to be the closest to capturing sound in the same way as our ears because they use a carbon ribbon to receive and project sound. Most are very delicate, however, and should not be used to record extremely loud singers.
Studio microphones used to commonly record the human voice have a wide variety of sound characteristics and pickup patterns. Some microphones work well for certain vocalists while others do not. Experimenting with different microphones for each singer and actively listening to the sound being captured will help you achieve the best results every time.