A quick comment on this thread. If you find thin, single poled crescents as opposed to dual-poled crescents (i.e., if you check one face of the crescent, and it has one N or S pole it is single poled as opposed to having a N on one end of the face and a S on the other end of the same crescent face which would be a dual poled unit.), you could easily use them to replace the ferrite magnets in the speaker if you just place a flux bar (soft iron, cast iron, steel, basically any ferrous, relatively high permeability metal) to fill the vertical height to make the combination height equal to the old ferrites being replaced. (look at following in fixed spacing type such as Courier or Line Printer) Sliced view from side of only 1/2 of a symmetrical structure +--Voice Coil Gap | V +--------+ +----------+ | | | | <---Original flux plate | | +----------| | | | | | | | | <---added flux conductor/spacer | | | | | | | | | | +--------+ | | | | <---new high energy magnet | +-----+--------+-+ | | | <-orginal lower flux plate +-------------------------+ P.S. You could use the dual-poled units by grinding a line on the face to mark two equal halves then snapping the magnet into two pieces by using a vise and a hammer or board. The magnets are brittle and don=92t bend, they break. Then you could lay up the magnet pieces with the poles all in one direction. Charles R. Patton _____________________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>