[zip22]

The difference between the ER-4S and the ER-4P is a resistor in each channel.
http://www.fixup.net/tips/ety/ety.htm

Is this the same as the difference between the ER-6 and the ER-6i? If so, I am curious what resistors would be needed to make the ER-6i into an ER-6.

edit: title should be "does the ER-6 = ER-6i + some resitors?"

 

[warpdriver]

According to Etymotic, the eartips aren't interchangeable, so I assume that the nozzles are also physically different in size.

 

[zip22]

has anyone taken apart the ER-6 or 6i?

 

[Teerawit]

I always thought that the er-6 and er-6i were pretty much different earphones altogether.