An agricultural harvester , comprising: a threshing system configured to receive crop material and to perform a threshing operation on the crop material, to generate threshed crop material; a first cleaning system (210-3) configured to receive the threshed crop material and to perform a first cleaning operation on the threshed crop material and to output the crop material from the first cleaning system (210-3); a first cleaning fan mounted to the agricultural harvester configured to direct airflow through the first cleaning system (210-3); a second cleaning system (210-4) configured to receive the crop material output from the first cleaning system (210-3) and to perform a second cleaning operation on the crop material; a second cleaning fan mounted to the agricultural harvester configured to direct airflow through the second cleaning system (210-4); a structural housing that defines a chamber with an inlet and an outlet, wherein the first cleaning system (210-3) and the second cleaning system (210-4) are disposed in respective portions (206-1, 206-2) of the chamber and wherein the first and second cleaning fans are positioned to direct airflow into the chamber to increase an internal pressure in the chamber; and a fan controller configured to generate fan control signals to control fan speed of the first and second cleaning fans , characterized in that the portions (206-1, 206-2) of the chamber are in fluidic communication with each such that a fan speed change of one fan will change the pressure in both portions (206-1 and 206-2) of the chamber and affect the airflow characteristics of the other fan , and that the second cleaning fan has substantially a same diameter as the first cleaning fan . a threshing system configured to receive crop material and to perform a threshing operation on the crop material, to generate threshed crop material; a first cleaning system (210-3) configured to receive the threshed crop material and to perform a first cleaning operation on the threshed crop material and to output the crop material from the first cleaning system (210-3); a first cleaning fan mounted to the agricultural harvester configured to direct airflow through the first cleaning system (210-3); a second cleaning system (210-4) configured to receive the crop material output from the first cleaning system (210-3) and to perform a second cleaning operation on the crop material; a second cleaning fan mounted to the agricultural harvester configured to direct airflow through the second cleaning system (210-4); a structural housing that defines a chamber with an inlet and an outlet, wherein the first cleaning system (210-3) and the second cleaning system (210-4) are disposed in respective portions (206-1, 206-2) of the chamber and wherein the first and second cleaning fans are positioned to direct airflow into the chamber to increase an internal pressure in the chamber; and a fan controller configured to generate fan control signals to control fan speed of the first and second cleaning fans , characterized in that the portions (206-1, 206-2) of the chamber are in fluidic communication with each such that a fan speed change of one fan will change the pressure in both portions (206-1 and 206-2) of the chamber and affect the airflow characteristics of the other fan , and that the second cleaning fan has substantially a same diameter as the first cleaning fan . <EOS>