Popular and traditional music
In many modern pop musical groups, a lead singer performs the primary vocals or melody of a song, as opposed to a backing singer who sings backup vocals or the harmony of a song. Backing vocalists sing some, but usually not all, parts of the song often singing only in a song's refrain or humming in the background. An exception is five-part gospel a cappella music, where the lead is the highest of the five voices and sings a descant, and not the melody. Some artists may sing both the lead and backing vocals on audio recordings by overlapping recorded vocal tracks. Popular music includes a range of vocal styles. Hip-hop uses rapping, the rhythmic delivery of rhymes in a rhythmic speech over a beat or without accompaniment. Some types of rapping consist mostly or entirely of speech and chanting, like the Jamaican "toasting". In some types of rapping, the performers may interpolate short sung or half-sung passages. Blues singing is based on the use of the blue notes–notes sung at a slightly lower pitch than that of the major scale for expressive purposes. In heavy metal and hardcore punk subgenres, vocal styles can include techniques such as screams, shouts, and unusual sounds such as the "death growl". Rapper Busta Rhymes performs in Las Vegas. One difference between live performances in the popular and Classical genres is that whereas Classical performers often sing without amplification in small- to mid-size hall , in popular music, a microphone and PA system (amplifier and speakers) are used in almost all performance venues, even a small coffee house. The use of the microphone has had several impacts on popular music. For one, it facilitated the development of intimate, expressive singing styles such as "crooning" which would not have enough projection and volume if done without a microphone. As well, pop singers who use microphones can do a range of other vocal styles that would not project without amplification, such as making whispering sounds, humming, and mixing half-sung and sung tones. As well, some performers use the microphone's response patterns to create effects, such as bringing the mic very close to the mouth to get an enhanced bass response, or, in the case of hip-hop beatboxers, doing plosive "p" and "b" sounds into the mic to create percussive effects. While some bands use backup singers who only sing when they are onstage, it is common for backup singers in popular music to have other roles. In many rock and metal bands, the musicians doing backup vocals also play instruments, such as rhythm guitar, electric bass, or drums. In Latin or Afro-Cuban groups, backup singers may play percussion instruments or shakers while singing. In some pop and hip-hop groups and in musical theater, the backup singers may be required to perform elaborately choreographed dance routines while they sing through headset microphones.