A standard AV receiver will usually suffice. Typically people with multiple speaker pairs such as yours use ‘zone 2’ (or ‘B’, if an A/B speaker option). A speaker selector connects there, and in your case, to the banana plugs in your wall.
In some cases where you want to maintain relatively high volume levels a secondary small amplifier is utilized via zone 2, between AV receiver and speaker selector.
Look at Russound equipment for this. Crutchfield usually carries some of their gear.
Questions? Feel free to ask.
I just bought a home that has several speakers mounted in the ceiling. There are 2 in the living room and 2 on the patio. In the living room there is a plate that has 8 banana clip style speaker jacks. I want to be able to play music through these speakers. I don't know to much about amplifiers and receivers, so I want to know what type of amp or receiver I need to purchase. Does it need to be 2 channels or 4 channels?

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