A spark plug center wire assembly that includes a noise suppressing conductive seal with improved isolation of the seal from the heat generated at the firing end of the spark plug. The center wire assembly includes a firing electrode, a conductive glass seal, an intermediate electrode, the noise suppressing glass seal, and a terminal electrode. By locating the firing electrode, conductive seal and intermediate electrode between the noise suppressing seal and the spark gap, the center wire assembly is able to utilize the noise suppression attributes of the suppressive seal, while distancing the seal from the high temperatures created during the combustion process. A method of manufacturing the same is also disclosed in which the two glass seals are formed by sequential firing operations.