This is very short and quick review. Hope I can update it when I have time. This is my standard cable to check audio source quality. Very accurate as well as close to my tympanum when I insert my ear like my Shure IEM (over the ear not straight down). Cord over the ear also offered me listening experience without touch noise. Now I am considering to re-cable it for balanced cable. Have not yet try ER-4SR, so I cannot compare them.

     To sum up, this is my another favorite beside Shure SE425 (my main IEM for 6 years) I have purchased this IEM at Yodobashi Camera by 18000 Japanese yen (about 160$ at the time) This is the top of the mountain of the sony dynamic in-ear. MDR-EX1000 are more spacial and musical in compare to this IEM, and EX600 (discontinued) is somehow bassy and entertaining.        The sound is very relaxing, but tight at the same time. I know it is contradictory. The mid-stage sound is very dynamic but delicate, and it never get you tired to listen music...

     Now, I own Sony MDR-EX800ST, Etymotic Research ER-4S, and Ultimate Ears Triple fi. 10PRO as daily use IEM. But still SE425 is my all time favorite for its accurate relaxing sound. I am a guy who always like to have music. I need music for walking, working, reading and forget about daily life. This is open like canal earphone. Sound is not too closed, bass is weak but deep, treble is transparent and relaxing.         I believe this SE425 has the best cost performance as your life partner through my 6 years of experience with this IEM. Of...