PURPOSE: To enable assembling of a magnet at high density, by a method wherein a hole is provided on a base so as to arrange two or more moving coils in one gap, springs of the two or mre coils are inserted in the hole, a parting member is provided between neighboring springs and fixed by resin.

CONSTITUTION: On a base 13 is provided a hole 14 sufficiently large to receive springs 8 of two or more moving coils. The springs 8 are inserted in the hole 14 and a parting member 15 is provided between neighboring springs 8 and fixed by resin 12. The parting member 15 is inserted in the hole 14 and slit (a) being nearly equal to thickness of the spring 8 is formed. Even if the spring 8 is inserted in the slit (a) and fixed by resin, it does not occur that the resin 12 is attracted by the parting member 15 and adhered and fixed to the spring 8.