Though some only know The Byrds for their covers, critics believe that they are amongst the most important and influential bands of the 1960s. Their signature sound of clear harmony singing and jangling guitars combined well with the sounds of British Invaders The Beatles & The Rolling Stones, and they became the pioneers of Folk Rock, Psychedelic Rock, Raga Rock, and Country Rock. The recording of the 1968 album The Notorious Byrd Brothers in the heyday of the Flower Power age was nothing less than Herculean; disputes over artistic direction & power struggles within the band meant that by the time recording was finished there were only two Byrd-members left. The album was a labour of love, though; it's more experimental and progressive than their previous works and is considered one of the best albums they made.