Abstract: A compressor may include a shell assembly, first and second scrolls, a floating seal assembly, a modulation-valve ring, and a modulation-control-valve assembly. The shell assembly may define a suction-pressure region. The first scroll may include a discharge passage, a modulation port, and a biasing passage. The modulation-valve ring may cooperate with the floating seal assembly and the first scroll to define an axial-biasing chamber in fluid communication with the biasing passage. The modulation-valve ring may be axially displaceable between a closed position to close the modulation port and an open position to open the modulation port. The modulation-control-valve assembly may be mounted to the modulation-valve ring and may be movable between a first position corresponding to the closed position and a second position corresponding to the open position.