You may have heard of Dr. Matti Otala of the Tampere University in Finland. Even if you haven't, the fine sound that the best transistor amplifiers are capable of today is a direct result of his pioneering work in the seventies on Transient Intermodulation (TIM). This is a type of distortion, previously unidentified, produced by early transistor amplifiers which made them so tiresome to listen to. Per Abrahamsen and Svein Erik Børja read Dr. Otala's paper and set out to design a transistor amplifier that would minimize TIM. Their 25 Watt amplifier, introduced in 1976 really did change the world and won their new Norwegian company, Electrocompaniet, many fans and customers including Bruce Swedian (Michael Jackson's producer). He used Electrocompaniet amps to master Michael Jackson's albums HIStory and Invincible. Electrocompaniet amplifiers found their way into many recording studios around the world including Abbey Road.
Original Resource is Enjoy The Music.com Audiophile