Professional musicians often receive instruction on proper microphone technique as part of their musical training, but very few karaoke or amateur singers get that kind of specialized instruction. As a result, amateur vocalists frequently encounter such frustrating problems as feedback, distortion and explosive "pops" of breath. There are a number of ways to eliminate, or at least substantially reduce, these kinds of unpleasant effects when using a vocal microphone. The microphone itself may not be the source of some performance problems, however, so it also pays to have a knowledgeable audio specialist on hand to handle the PA system and mixing board.
- Adjust the microphone stand, not just the microphone. Many sound systems have microphones mounted on adjustable microphone stands. There are two very common types of microphone stands a karaoke or amateur singer may encounter. One is a telescoping vertical pipe with a heavy base and an adjustable clamp in the middle. You should loosen this clamp by twisting it counterclockwise while holding the top section firmly. Once the top section moves freely, raise or lower it until the microphone is just below mouth level. Tighten the central clamp by turning it clockwise, then make smaller adjustments by raising or lowering the collar around the microphone itself. You can also move the stand back and forth until it is approximately 4 to 6 inches from your mouth and angled upwards. If you hear distortion or lower volume during your performance, you can back away or move closer to the microphone as needed. Try not to move the microphone stand itself during a vocal performance, since any extraneous noise will be amplified.
The other type of microphone stand consists of two metal tubes held together at an angle by a clamp. This type of microphone stand is more often used to amplify musical instruments, but it can also be used for vocalists. To adjust this type of microphone stand, you may need to set the base slightly off-center and loosen the clamp to make both vertical and horizontal adjustments. Fine tune your microphone's distance from your mouth by angling the collar around ithe base of the microphone. Tighten all of the clamps before performing, since these types of microphone stands have a tendency to slip out of place.
- Use vocal monitors whenever possible. Microphones are great for amplifying your voice through main speakers and out to the audience. What is harder to gauge is how the music and vocals are mixed while you perform. This is why you'll want some form of vocal monitoring. Some sound engineers will set up a smaller amplifier near the vocalist and feed a mix of the music and vocal into it, while others may provide a headphone or earphone with the same audio feed. What you hear coming out of that vocal monitor should be approximately what the audience is hearing through the main speakers. If you can't hear yourself at all or you sound distorted, you are most likely out of range of the microphone. Use the vocal monitor to let you know when you are in the best place for the microphone to amplify your voice.
- Never get the microphone out of position. Feedback and explosive "pops" are very unpleasant for the audience to hear, so you should always make an effort to keep the microphone out of the danger zone. One such zone is the area directly in front of a main speaker or vocal monitor. A small electronic hum could enter the microphone and become amplified. This amplified hum loops back into the speaker and is amplified even more. The result of all this looping and amplification is called feedback, and it can get very loud very quickly. Feedback can also be caused by holding a live microphone at an extreme downward angle. If you hear feedback forming while singing, step away from any nearby speaker until the squeaking subsides. A sound engineer may turn down the volume of the main speakers or the power to the microphone until the feedback ceases.
Another problem caused by improper distance between you and your microphone is explosive pops. This can be more of a problem when recording, but it can also affect live performances. Certain consonant sounds like "P" and "T" can come across as loud pops if the microphone is held too close to the performer's mouth. One solution is to adjust the microphone so it angles up from below the singers jawline, not directly in front of his or her mouth. The explosive air does not strike the microphone at such a direct angle that way.
- If you use a hand-held microphone, keep your distance. Holding a microphone in your hand does not change the basic rules of microphone usage. You still need to maintain an acceptable distance between your mouth and the microphone, and you must still be diligent about feedback and extreme angles. If you are a power singer by nature or need to perform a very loud passage during the song, you may want to back away from the microphone to avoid distortion and oversinging. Professional-grade microphones can still keep power notes and loud vocal runs in proper balance if you pull away at the right angle. Avoid pointing the head of the microphone to the extreme left or right to avoid total loss of volume.
- To test a microphone, simply speak into it until it is properly adjusted. Do not blow into a microphone as a vocal test, because the sensitive filaments inside may become damaged. Tapping a microphone with your fingers is also a bad idea, since tapping only proves the microphone is energized, not balanced out in the mixing board. To test a microphone, simply speak into it at a normal vocal level. "Testing one, two, three" may be all the words a sound engineer needs to hear. If you plan on performing in a more powerful vocal style, you may want to sing a few lines of your song at the level you plan on using during the song. This will help the sound engineer balance out the amplification range of the microphone to avoid distortion or feedback.
Because different venues have different set-ups for vocalists, you may want to familiarize yourself with all the different types of microphones and stands out there. Some places may allow you to make necessary adjustments yourself, while others may have a person assigned to that detail. You may be handed a wireless microphone, but that does not necessarily give you a ticket out of the center spotlight. If you cannot adjust the microphone or the stand, you may have to adjust yourself accordingly. Make sure you know how to turn the microphone on or off, and always remember a live microphone will pick up every word you utter into it.