Upper frequency response through the SRH1440s was open and extended without sounding hyped-up. Violins and flutes never sounded strained or metallic (except when that was the player’s intent.) On classical recordings with a lot of room ambience the SRH1440s upper frequency response generated a larger and more open room acoustic than the A-T W-3000ANV headphones. The AKG K-701’s upper frequency response was much closer to the SRH1440’s, but their leaner midrange and upper bass sounded slightly astringent in comparison to the SRH1440s.
Due in part to their upper frequency extension, the SRH1440s image beautifully. The overall soundstage was as big as the AKG K-701s, but with better three-dimensionality and imaging specificity. Grado’s RS-1 headphones generated a similarly sized, outside the head, soundstage, but with slightly greater midrange proximity and prominence. The only earphones in my reference collection that delivered better, more precise and dimensionally accurate imaging were the Ultimate Ears In Ear Reference Monitors.
The amount of low-level detail delivered by the SRH1140s was noticeably superior to the Sennheiser HD600s, especially on lower frequencies. To find a headphone that had the same amount of inner detail I had to move up to the Grado RS-1 headphones or the Ultimate Ears IERMs. During multi-hour monitoring sessions the comfort of the SRH1440s quickly brought them to the top of my grab-first list over the Grados and UEs.
Dynamics from the SRH1440s was always convincing with excellent contrast. Micro-dynamics were especially well handled, regardless of the amplifier, but macro dynamics were influenced by an amplifier’s quality and ability to deliver wide voltage swings. Triple fortes were far more impressive through the April Music Eximus DP-1 headphone amplifier than through a 4th generation iPod Touch. Given their sensitivity and impedance the SRH1440s should be easy for any decent headphone amplifier section to drive, but the Shures will definitely reward listeners who use something better than the headphone amplifier found in a typical portable MP3 player.