This RCA male to two RCA female adapter can be used by one source channel to drive two amp channels. https://www.amazon.com/MyCableMart-Female-Piggy-Back-Splitter-PREMIUM/dp/B0147LDZ72/
This RCA male to two RCA female adapter can be used by one source channel to drive two amp channels. https://www.amazon.com/MyCableMart-Female-Piggy-Back-Splitter-PREMIUM/dp/B0147LDZ72/