Hi,
Does anybody have SQN 4s series III owners manual or maybe know where to find one?
Couldn't find any in eBay and Google gives only 4s series IV manual.
The company is still very much in business, with a Web site on www.sqn.co.uk . In the United States (assuming that's where you are), Trew Audio is a dealer for them, and might be able to help you with information.
--best regards