Some of his greater successes include the hits Meu Bem – a Portuguese version of The Beatles' Girl – and A Praça.
He quickly earned the nickname O pequeno príncipe, or Little Prince, after participating in an interview with Hebe Camargo.
During this period, the press tried to create a supposed rivalry between him and Roberto Carlos.
In 1968, he released a self-titled album that broke from the naïveté of his previous work and ventured in more psychedelic and experimental sounds.
Though it did not meet with much success, today Ronnie's experimental work is being rediscovered by a new generation of rock listeners, rendering him a high degree of underground cult status.