BRG was elevated to one of the leading positions in Hungarian and Central European tape recorder manufacturing by Chief Engineer Marcell Jánosi and his team. While the earlier mentioned Mambo was developed under license, the M8 „Calypso,” a three-speed tape recorder, marked the beginning of fully independent Hungarian tape recorder production in 1961-62. The chassis of this model, developed taking full advantage of BRG’s technological capabilities, served as the basis for reel-to-reel tape recorders in the following years. Alongside the M8, development continued with the M10, which was a quarter-track version, followed by the M9 and its quarter-track variant, the M14, and subsequently the M20 and M40. The base model was also marketed by the West German Quelle retail chain under the names M2 and M4 Revue, proving the devices were modern for their time. As reel-to-reel tape recorders transitioned to cassette recorders, BRG developed the M11, a unique combination of two tape recorder types. There was also a stereo model, the M12, but unfortunately it could not go into mass production due to an incomprehensible decision by Comecon, which allocated reel-to-reel tape recorder production to other countries. Therefore, after this, BRG could only manufacture cassette recorders.