The radiolas were perhaps the first radios that existed. They were a kind of small furniture containing a transistor radio; which appeared later, brought a built-in player; later, with the emergence of cassettes, appeared also the early sound equipment, containing a radio to tune in to stations. M. a turntable and a unit for cassettes, at the same time seemed the radio-grabadoras or radio-cassette sets which could tune in to stations. M. and F. M. and with one or two drives for cassettes; then appeared the sound equipment that we know today, devoid of turntable but provided three units for CD, in some cases.