What does the i stand for in the new SR325is from Grado? enhanced, thats what! Yes, Grado has taken one of the worlds most acclaimed headphones & taken it a few steps further. The new SR325is has an upgraded driver & cable design. The way the SR325is&8217; driver, cable & metal housing move air & react to sound vibrations are now less affected by transient distortions. With the new 8 conductor cable design you will notice enhanced control & stability of the upper & lower range of the frequency spectrum with both better supporting Grados world renowned midrange. The SR325is will produce a sound that is pure Grado, warm harmonic color, rich full bodied vocals, excellent dynamics & an ultra smooth top end. Listen & Enjoy!