An electrical connector includes a housing, plural signal contacts, and plural impedance control (IC) members. The housing includes a base having a mating face. The base includes an array of openings along the mating face. The signal contacts are arranged in contact pairs, and are held in the openings of the base. The signal contacts include mating segments that extend a height beyond the mating face of the base for electrically connecting to corresponding mating signal contacts of a mating connector. The IC members are on the base and extend a height beyond the mating face of the base that is less than the height of the mating segments of the signal contacts. Each of the IC members is disposed one or more of adjacent to or between the signal contacts of a corresponding contact pair.