Is this what you have? If it is then you can see that's NOT a SW.
https://www.google.com/search?q=acoustimass+5+series+3+sub+connections&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwilgca89pHLAhVBxGMKHaAXDnsQ7AkIZA&biw=1038&bih=500#imgrc=K4q9taOexevxSM%3A
I have an older Bose Acoustimass 5 Series III subwoofer with the 5-pin DIN connector to the subwoofer and the corresponding other end to the receiver is 2-RCA jacks and a small mini audio 3.5mm jack (it looks like).
My ?- is the input (RCA jacks from my receiver) to the subwoofer line level or speaker-level / audio level? Can I just cut the RCA jacks off, tin the ends and connect them to the L+R speaker out jacks on my receiver?
The Acoustimass 5 Series III was designed to be used with other receivers / amps than Bose but I suspect they sold a conversion cable? or?
The only online manual is for the later (2001 pub date) Series III subwoofer where Bose replaced the 5-pin DIN input with two spring clip speaker wire inputs on the subwoofer...sooooo I suspect I can do what I think?

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