A baler for use with a forming bale having a first bale attribute. The baler including a frame, and a compression system coupled to the frame where the compression system at least partially defines a compression chamber sized to receive at least a portion of the forming bale therein. The baler also includes a feed pan at least partially defining a pre-compression chamber, and where the shape of the pre-compression is adjustable, and where the pre-compression chamber is open to the compression chamber. The baler also includes a sensor configured to output signals representative of the first bale attribute, and a controller in operable communication with the feed pan and the sensor, and where the controller is configured to actively adjust the shape of the pre-compression chamber based at least in part upon the first bale attribute of the forming bale.
