history. Rock was seen as subversive by the nation's authority figures, who began to clamp down on the music. In a 1976 speech, Admiral Emilio Massera denounced rock musicians and fans as potential subversives and repression of them began in 1977. Before the end of the decade, rock had gone increasingly underground. Rock Nacional avoided the government's heavy media censorship and allowed an outlet for codified criticism of the government. In spite of this however, the music would continue its development against the odds. Along with the plethora of symphonic/progressive bands, heavies Vox Dei and Pappo's Blues continued to sustain their popularity during the period. Yet another heavy metal band, Plus, made their debut in '76 and enjoyed success through the end of the decade. Symphonic rock at late 1970s Argentine rock continued its symphonic, so-called 'concert hall' sound through the end of the decade. The '78-'79 period was not the most prolific period for rock, as the progressive bands continued with their blueprint, and symphonic rock bands actually turned slightly commercial. At the height of symphonic rock, Crucis was joined at the top by the popularity of Espíritu; the two are generally seen as the most well-known outfits of the symphonic rock period. The first album of La Máquina de Hacer Pájaros was a mixture of effort, individual performances, melodies, dynamic contrasts, ensemble work and arrangements. 1977 was a year of separation and endings: Crucis would disband at the end of the year. In heavy metal, Pappo's blues would see their nearly seven-year run end. Aquelarre would return from their Spanish stint, but following a tour run went their separate ways. But the year would show a glimpse at the future: a band from La Plata called Patricio Rey y sus Redonditos de Ricota, with their comical costumes and nervy fast tempos, started performing. 1977 was a year in which certain bands had a short period of fame: Soluna (Gustavo Santaolalla's 2nd group), with their electric folk, and Orion's Beethoven, a progressive band that played since 1969 but had their moment of fame eight years later. Neither band sustained their popularity into 1978. Bubu with their album Anabelas, in 1978 was one of those bands too. And even more bands ceased to be. After two successful albums that featured several would-be classics of the era, La Máquina de Hacer Pájaros hung up, as did Invisible, leaving as a legacy