I have heard rumors that a 416 Alnico version is in the pipeline but never heard it was available yet. I would think if they build a 416 Alnico that the 604 won't be far behind.
On another note, all of my altecs are vintage alnicos so I can't honestly say I have any info to offer either positive or negative about ferrite motors.
Other threads have discussed the differences and I believe cost is the factor holding up the reissue of alnico.
Gary
