T + A was the first High-End manufacturers to equip a CD player with additional digital sources. The idea was unusual at the time, but it was certainly logical and justified. Our first machine to incorporate the principle was the E-Series Music Player. The sound quality of a digital music source is determined to a great extent by the quality of the digital-to-analogue converter (DAC) employed. Since T+A CD players had always boasted excellent converters, it made a good deal of sense to add additional digital sources to them, such as a network streaming client, a tuner and various inputs for external digital sources, instead of producing a separate case for each individual source.