N3000-E vs N3000-F

[Drugolf]

Anybody know what the difference is between the two designations on the 3000? Using these with 601C.

[Johnny_Law]

Been poking around trying to help ... there ain't much out there.

https://www.audioasylum.com/cgi/t.mpl?f=hug&m=129481

http://www.steampoweredradio.com/pdf/altec/altec%201965.pdf

https://audiokarma.org/forums/index.php?threads/altec-n-3000f-xo-rebuild.149885/

http://www.audioheritage.org/vbulletin/showthread.php?7257-n-3000-xover-schematic-for-601c-Altec