Complex sentence: Although the band's expanding musical boundaries were greeted warmly by some, detractors attacked the heavier tracks as being mindless noise, while the acoustic material was criticised by others for merely imitating the music of Crosby, Stills, Nash & Young.
Split into simpler sentences: Although the band's expanding musical boundaries were greeted warmly by some, detractors attacked the heavier tracks as being mindless noise. Others criticised the acoustic material for merely imitating the music of Crosby, Stills, Nash & Young.