Marantz 2226


I have a Marantz 2226 receiver I cleaned up and plan on using in a small bedroom system. On the back panel is connections that say:

MAIN IN PRE OUT

Anyone know if I should throw a set of jumpers between these? Any and all responses will be appreciated.
Thanks
sprink
Pretty sure you don't need to.... Early Marantz Receivers yes. 1979 I don't think so. Hook up the receiver first and try it. No sound install the jumpers
Marantz 2226

Vintage Marantz
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I have sound. Actually sounds pretty good. Why my lazy a$$ didn't just plug it in and try it in the first place is beyond me. Thanks for your response.