Etymotic ER4 Conversion Cable
Genuine Etymotic Research Cable Adaptor to convert ER-4PT earphones to ER-4S or the other way around.
The inline adapter converts the response accuracy of the ER - 4PT from 86% to 92%.
ER4S earphones are designed to compensate for the high frequency emphasis in all CD recordings, in order to provide accurate sound reproduction. Performing musicians often use them as in-ear monitors because the response of the ER4S matches the response of most typical monitor loudspeakers. The high accuracy and exceptional sound isolation of the ER4 range have made these earphones popular with musicians, recording engineers and audiophiles.