 In "Sessions with Sinatra; Frank Sinatra and the Art of Recording", Sinatra historian Chuck Granata observes "In Slatkin, Sinatra found a kindred spirit, as the violinist's immaculate playing paralleled what Sinatra sought to achieve with his voice; serious listeners will note many similarities comparing Sinatra's and Slatkin's individual approaches to musical interpretation.One hallmark of the HSQ was its long, smooth phrasing which was accomplished through controlled bowing techniques; Sinatra utilized breath control to realize the same effect.Likewise where Felix would frequently add slight upward portamento to a critical note and neatly strike an emotional chord, the singer would often inflect a note upward or downward or seamlessly glide from one key to another."