The present invention is a method of compressing lamination stacks for a permanent magnet rotor. The matrix comprises a first string of stations and a second string of stations where the first and second strings have the same number of stations. Those audio signal output terminals provided for plural channels of the audio signal output apparatus are arranged to enable an user to discern individual audio signal output terminals by the color added thereto. In preferred embodiments, residual salt water which is heated by heat given off during formation of the hydrate is removed from the system to create a bias towards overall cooling as the hydrate dissociates endothermically at shallower depths. Thus, the nut 73 is caused to ascend in the axial direction along the screw segment of the feeding screw shaft 71 so that the column 4 can be tiltingly moved downward. The separated fibers are fed to a conveyor moving in a conveying direction such that the separated fibers form the nonwoven.