Thank you for your responses on the subject. I have remained surprisingly indifferent to the Etymotic Research earphones. To review the product, I have used a selection of recordings that I a familiar with and also have used a range of reference classical and jazz genre sound recordings. While I find the earphones to be quite detailed in a specific range of frequencies, in a general sense I dont find their presentation as complete as I tend to desire. In certain recordings, lower frequencies (bass impact/ slam) seems to be inadequate and the result is that the total presentation in my view is thus quite insipid. I should note that I am not using the Eytmotic Research earphones with an amplifier or the ER4P-24 cable. If either or both of these is a solution, then I would welcome suggestions on an amplifier that is well matched to both Etymotic Research and Grado Labs headphones. I also have not specified any source information as it ranges from an Apple iPod, PowerBook G4, or equipment in my home or work place. In returning to the original threat topic, will the ER4P-24 cable provide the results I am seeking?