all except for Arcaño himself. He decided not to have a singer (vocalists were popular in danzón since 1929) and decided to play mostly black venues, which paid significantly less than whites-only clubs. Nonetheless, this allowed the group to learn their trade and became particularly prolific: one year they performed a record 404 shows in total. Every night, las Maravillas would play in a different venue, including casinos, hotels, youth associations, blacks associations, etc. Their long sets required them to have a vast repertoire, but thankfully most of its musicians were also composers. The brothers Cachao and Orestes would compose new danzones regularly, totalling thousands over the years. Many of these were dedicated to the venues they performed in, such as "Social Club Buenavista" (in Buenavista, Havana) "Club Social de Marianao" (in Marianao, Havana), "Redención Sport Club" (in Pogolotti, Havana), "Juventud de Pueblo Nuevo" (in Pueblo Nuevo, Havana), "Avance Juvenil" (in Ciego de Ávila), "Centro San Agustín" (in Alquízar) and "Bella Unión" (in Güines). The band's first big hit came with "Mambo", a danzón de nuevo ritmo, or as it would be called later, danzón-mambo. This style, created by the López brothers, added an improvised section to the end of the danzón structure. This section, the "mambo", proved to be very popular with dancers, as it allowed them a certain freedom not present in the rigid structure of the danzón. New genres would later emerge from this section, such as the fast-paced mambo and the slower chachachá, both of which became dance crazes in the 1950s. They made their first recordings in April 1940, and in 1944 the group expanded its lineup for the radio, where they had their own program on Radio Mil Diez, sponsored by Gravi toothpaste and Dermos soap. This group was known as La Radiofónica. At this point, the group was competing with the most popular ensembles of the island, and together with Orquesta Melodías del 40 and Arsenio Rodríguez's conjunto it formed Los Tres Grandes (The Big Three). In 1945, circulatory problems related to his lip prevented Arcaño from maintaining his embouchure, which was the end for his playing career. He continued as director and hired his cousin and former teacher José Antonio Díaz as flautist, who was later replaced by Eulogio Ortiz. It was Ortiz who recorded the 1951 version of "Mambo". Cachao left the group by the end of the decade (being replaced