Music played an integral role in religious rituals among all classes of Aztec society. Instruments dating to 2500 BCE or earlier provide evidence for music culture in the region, but musical activity likely began much earlier. Music was used in the temples, palaces, and the homes of commoners to facilitate ritual activity. Musicians held a high status in Aztec society, and their education was extremely strict. Aztecs sang, and used percussion and wind instruments, but there is no evidence of string instruments in the Pre-Columbian Americas. The words of many songs survive across several codices, sometimes along with their composers' names, but there is no consensus on what additional markings in these manuscripts meant or exactly how the music sounded. Aztec musical culture influenced and was influenced by other Mesoamerican cultures through migration, trade, and invasion.

Overview Much of what is known about Aztec music comes from surviving instruments, the accounts of Spanish chroniclers, modern recordings of traditional music, and a variety of codices that illustrate musical activity before and after the Spanish arrived. A large body of music-related artifacts, discovered among the temple ruins of Tenochtitlán (CE 1325-1521), provide evidence of how music was organized in Aztec thought. In Tenochtitlán and surrounding cities, priests were responsible for playing music while attending to their ritual duties, and musicians were responsible for sounding the call to prayer four times a day and five times a night.

Uses of Music

Music was strongly identified with religion in Aztec life, and was not used in secular contexts. Martens explained the link between music, dance, and ritual: In Aztec society, music was usually a group activity and less often a means for individual expression. Some musical instruments were worshipped in the temples of Tenochtitlán. Aztec mythology regarded drums as associated with the sun and shell trumpets with the moon. The Aztec god of music was Macuilxochitl ("5-Flower") or Xochipilli ("Prince of the Flowers"), to whom at least three temples were dedicated in Tenochtitlán.

Temple and Palace Multiple times per day, Aztecs engaged in collective, ritualized crying to implore their gods for forgiveness. In some rituals, periods of crying were interleaved with silence. After these solemn festivals, Aztecs sang, played instruments, and danced to songs that gradually increased their pitch and tempo. A ritual depicted in the Codex Mendoza includes nightly sacrificial rites, initially accompanied by wind instruments, followed by drums and chants. Prior to being sacrificed, a woman representing the goddess Xilonen would shake a rattle stick while wearing garments with bells. A ritual cycle concluded with the destruction of the instruments used.

Singers, musicians, and dancers played an important role in the coronation of the new tlatoani. Here, the tlatoque of Texcoco and Tlacopan led a dance in the palace, joined by 2,000 high-ranking guests bringing lavish gifts. The huehuetl was used during the tlatoani's dramatic entrance. Emperor Ahuitzotl (1440 CE – 1502 CE) was fond of music and used it for continuous entertainment in his house at all times of the day and night.

Household Music accompanied almost all ritual activity in the home, and household excavations have revealed musical instruments. For example, houses in Xaltocan dating to the Middle to Late Postclassic period, as well as other sites, contained rattles that take various shapes, such as figurines, spheres with handles, or incense burner handles. Some female figurine rattles may have been used by midwives to assist the birthing process by helping the woman in labor to focus on rhythmic sounds. Ceramic flutes were decorated with flowers on the end to represent instrumental music, or "flowery song" (xochicuicatl). Human femurs, sometimes from sacrificed enemies, were fashioned into bone rasps inside the home, and the rasps were used at funerals and possibly other occasions. Other instruments uncovered within homes include flutes and whistles. Feasts were held in the home to commemorate life and calendrical events, where music and dance were common.

Military Songs formed an important part of warrior training and were sung together by boys of different ages at the calmecac. During the imperial period, song themes and singing technique adopted a militaristic tone. Aztec military instruments included drums, conch shells, and whistles, and there was a band for each regiment in the Aztec army. The Aztec war drum was called tlalpanhuehuetl. During the siege of Tenochtitlán, singing was part of battle. Both the Spanish and the Aztecs sang, and "It was if both sides were challenging each other with their songs." Moreover, singing was used to help defend the city and provide warning of approaching enemies; young men in school were selected to sing in the evenings to keep watch.

Education Aztec schools for upper class children or gifted commoners were called calmecac, and included music education. Teachers, known as Tlamacazque, would teach children "divine songs", while Tlapizcatzin prepared musicians for religious services, and Ome Tochtzin managed musical performances. The calmécac in Tenochtitlán served as the national music conservatory for the Aztecs, and by 1450 CE it was a model for music schools in surrounding cities. Music education in Aztec society was extremely rigid:

In Texcoco and Tacuba, music and dance were taught in schools called cuicacalli ("the house of songs"). In the cuicacalli, distinct professionals played different roles. The cuicapiqui developed themes, the cuicano composed the text and music, and other directors managed music and choreography. Boys and girls attended public schools called techputcalli which included instruction in singing and playing instruments. Convent schools, attended by girls of high social status, prominently featured music education and included instruction from priests in singing, drumming, and flute playing. Public schools for both music and eloquence flourished.

The huehuetl drumming patterns may have been learned with a system of syllables, such as to and co for low pitches and ti and qui for high pitches. Thus a certain drumming pattern could be memorized by reciting "toto tiquiti tiquiti".

Musicians Court and temple musicians held high status, mingled with the powerful, and were exempt from paying tribute because of "their service to the community in preserving the memory of past glories." Since the Aztecs didn't use written music notation, musicians needed exceptionally good memories to perform; creativity was also prized. Despite this high prestige, no names of musicians are known. Náhuatl did not have a general term for musician, but instead many terms for specific types of players.

Instruments

Aztec instruments have a long continuous history beginning c. 2500 BCE. They include voice, idiophones, membranophones, and aerophones. Ideophones and membranophones included drums, rattles, clattering instruments, and metallic instruments. Aerophones included trumpets and flutes. There is no evidence of string instruments among the Aztecs, with the possible exception of a musical bow.

The Aztecs used a variety of materials in making instruments. Drums and rattles were made of dried seed pods, conch shell, gold and copper alloy bells, ceramics, gourd, wood sticks, human femurs, deer shoulder blades, turtle shells, and stone. Drums beaten with the hands were covered with deer, coyote, ocelot, and jaguar hides. Trumpets were made of shell, ceramics, and vegetable material. Flutes were made of bone, reed, ceramic, and stone, and other aeorphones included whistles made of ceramics and skull. Aztec metalworkers made instruments such as the ayachitlitzi, chichahuazi, and trumpets. There is evidence that Aztecs classified their instruments into two main groups, distinguishable by the terminology for the player, such as a "drum beater" (hue-huetzotzonani), and "shell trumpet blower" (quiquizoani). In Aztec musical thought, instruments may have been classified according to the material they are made of or their symbolism. For example, drums and metallic sounds suggested royalty, fire, and the sun; shell trumpets suggested the moon and underworld.

Voice The hierarchy of singers in Aztec music culture was recognizable to the Spanish when they arrived, and included positions that corresponded to the precentor, succentor, and choir.

Percussion Aztec music was dominated by percussion, and the Aztecs tuned their drums carefully to produce bold, loud, and high pitched sounds that could be heard by the gods. Idiophones included various rattles, such as those made with seed pods, ceramic vessels, and gourds. Rattles were sometimes made into figurines or incense ladles. They also used rows of metal bells. A rattle stick painted blue called ayauhchicahuaztli ("instrument to strengthen the fog") was meant to ask the god Tlaloc for rain.

Two of the most important Aztec drums include a slit-drum called a teponaztli played with mallets, and an upright drum called huéhuetl played with the hands. These drums were believed to be both musical instruments and gods "temporarily forced to endure earthly exile." In one telling of the myth, Teponaztli and Huehuetl were servants of the sun god who were banished to earth and made into the form of the instruments. The huéhuetl is a vertical drum made of wood, open at the bottom, and covered in jaguar or deer skin. The player beats the drums with the hand, adjusting pitch by drumming near or far from the center; tuning was achieved by heating the skin to tighten it. The teponaztli was a horizontal slit drum, made of tree trunk or stone, and cut into an 'H' shape to produce two tongues that produce a pitch when struck with a rubber-tipped mallet (olmaitl). The tongues were tuned to octaves, minor 3rds, major 2nds, or perfect 5ths. The drum has been described as producing a sad and far-reaching sound. Both of these drums are still in use today.

Wind Trumpets were made of shell, ceramic, plants, or metal. Flutes were made of bone, reed, ceramic, and stone. Skull whistles were accoustically designed to produce an unusual wind-like sound.

Aztecs used several types of flute (modern Nahuatl: huilacapitztli) made of clay, reed, and bone. The çoçoloctli was a ceramic spherical vessel flute containing between 5 and 8 holes. The tlapitzalli is an end-blown flute whose forms included straight, curved, and Y-shaped; it included a mouthpiece and a flared end, and was sometimes painted and decorated. A sacrificial victim played these instruments while ascending the pyramid steps, then broke the flutes prior to his sacrifice. The chichtli (or tlantquiquitli) was a whistle also connected to sacrifice, blown the night prior as the victims' hair was pulled from their heads. A 'royal flute' was another end-blown flute with a single chamber and 4 finger holes. The Aztecs attached the sac of a spider's egg over a hole near the mouthpiece, giving the instrument a distinctive buzzing sound.

The Aztecs referred to their conch shell trumpet (atecocoli), usually played in pairs, as ‘Wind God Quetzalcoatl; he who breathes life into a void’. The tecciztli and quiquiztli were similar wind instruments made from the shells of Strombus gigas and Fasciolaria gigantea, respectively. They were played by priests as calls to prayer as well as to mark sacrificial events.

The Aztec skull whistle produced a wind or hissing sound with low air pressure, but a "shrill, piercing, and scream-like sound" with high air pressure. The psychoacoustic properties of skull whistles have been studied. Sound recordings from two whistles from the Tlatelolco archeological site, Mexico City dating to 1250 CE – 1521 CE were obtained and played back to modern Europeans, who described the sound as scary and aversive. These whistles were likely used for ritual rather than warfare.