An insulative feedthrough that is configured to be attachable to an active implantable medical device (AIMD), the insulative feedthrough comprising: a) a conductive ferrule comprising a ferrule first side opposite a ferrule second side, the ferrule defining a ferrule opening extending to the ferrule first and second sides; b) an insulative feedthrough body comprising a material which is both electrically insulative and biocompatible, wherein the insulative feedthrough body is at least partially disposed within the ferrule opening where the insulative feedthrough body is hermetically sealed to the ferrule, the insulative feedthrough body having an insulative feedthrough body body fluid side spaced from an insulative feedthrough body device side; c) a passageway disposed through the insulative feedthrough body, the passageway extending from the insulative feedthrough body body fluid side to the insulative feedthrough body device side, wherein an internal metallization is formed on an inner surface of the passageway; d) a composite conductor disposed within the passageway, the composite conductor comprising: i) a body fluid side metallic wire having a body fluid side metallic wire first end disposed inside the passageway and a body fluid side metallic wire second end, wherein the body fluid side metallic wire is biocompatible; ii) a device side metallic wire which is not of the same material as the body fluid side metallic wire, the device side metallic wire having a device side metallic wire first end disposed inside the passageway and a device side metallic wire second end, wherein the body fluid side metallic wire first end is disposed at or adjacent to the device side metallic wire first end in the passageway extending through the insulative feedthrough body; and iii) a first braze contacting the body fluid side metallic wire first end, the device side metallic wire first end and the internal metallization, the first braze forming a first hermetic seal separating the insulative feedthrough body body fluid side from the insulative feedthrough body device side in the passageway extending through the insulative feedthrough body. a) a conductive ferrule comprising a ferrule first side opposite a ferrule second side, the ferrule defining a ferrule opening extending to the ferrule first and second sides; b) an insulative feedthrough body comprising a material which is both electrically insulative and biocompatible, wherein the insulative feedthrough body is at least partially disposed within the ferrule opening where the insulative feedthrough body is hermetically sealed to the ferrule, the insulative feedthrough body having an insulative feedthrough body body fluid side spaced from an insulative feedthrough body device side; c) a passageway disposed through the insulative feedthrough body, the passageway extending from the insulative feedthrough body body fluid side to the insulative feedthrough body device side, wherein an internal metallization is formed on an inner surface of the passageway; d) a composite conductor disposed within the passageway, the composite conductor comprising: i) a body fluid side metallic wire having a body fluid side metallic wire first end disposed inside the passageway and a body fluid side metallic wire second end, wherein the body fluid side metallic wire is biocompatible; ii) a device side metallic wire which is not of the same material as the body fluid side metallic wire, the device side metallic wire having a device side metallic wire first end disposed inside the passageway and a device side metallic wire second end, wherein the body fluid side metallic wire first end is disposed at or adjacent to the device side metallic wire first end in the passageway extending through the insulative feedthrough body; and iii) a first braze contacting the body fluid side metallic wire first end, the device side metallic wire first end and the internal metallization, the first braze forming a first hermetic seal separating the insulative feedthrough body body fluid side from the insulative feedthrough body device side in the passageway extending through the insulative feedthrough body. i) a body fluid side metallic wire having a body fluid side metallic wire first end disposed inside the passageway and a body fluid side metallic wire second end, wherein the body fluid side metallic wire is biocompatible; ii) a device side metallic wire which is not of the same material as the body fluid side metallic wire, the device side metallic wire having a device side metallic wire first end disposed inside the passageway and a device side metallic wire second end, wherein the body fluid side metallic wire first end is disposed at or adjacent to the device side metallic wire first end in the passageway extending through the insulative feedthrough body; and iii) a first braze contacting the body fluid side metallic wire first end, the device side metallic wire first end and the internal metallization, the first braze forming a first hermetic seal separating the insulative feedthrough body body fluid side from the insulative feedthrough body device side in the passageway extending through the insulative feedthrough body.