A logical pipeline or logical hybrid pipeline is used for an xDSL communication system, and particularly for processing DMT symbols. This flexible arrangement permits easy and efficient sequencing of DMT symbols for transmit/receive tasks, and for multiple ports, since the pipeline resources can be shared or allocated as needed to support a particular data transmission. Each stage in the pipelines works on input data objects, and creates output data objects in the same format for use by other stages. The data objects are based on DMT symbols, so this facilitates intelligent control and sequencing of a DMT data transmission. The combination of the pipeline and the tailored data objects permits an implementation of a customized xDSL symbol processor.