A cable assembly includes a plurality of electrical or fiber-optic cables, a spacer, and a collar. The cables are arranged lengthwise in a bundle, which includes a segment having a cross-sectional arrangement organized into a plurality of columnar sections of contiguous cables. Each columnar section has at least one cable. The spacer is disposed between the adjacent columnar sections. The spacer spans substantially entirely across a cross section of the segment of the bundle in one direction. The collar is disposed entirely around the bundle and the spacer along at least a portion of the segment. The collar is sufficiently tight such that the collar and the spacer cooperate to hold the adjacent columnar sections in substantially fixed relative positions within the cross-section of the bundle.
