Complex sentence: In 1957, the company made history when they released Quad Electrostatic Loudspeaker (ESL), the world's first production full frequency range electrostatic loudspeaker renowned for sonic transparency and very low distortion.
Split into simpler sentences: In 1957, the company made history when they released Quad Electrostatic Loudspeaker, the world's first production full frequency range electrostatic loudspeaker. The ESL is renowned for sonic transparency and very low distortion.