Association of Moving Image Archivists AMIA — has email list AMIA-L
Association of Recorded Sound Collections ARSC — has email list ARSCLIST
Lists for a specific manufacturer’s machines
Ampex information at recordist.com — has email list AMPEX
There is a consumer-oriented Nakamichi list here
Studer information at recordist.com — There is a new iteration of this email list STUDER
There is a new STUDER list at YahooGroups.
Sony and MCI recorder email list (listowner is also owner of these Web pages)
Otari Equipment email list
SCULLY email list