onkyo tx-nr905

I have an Onkyo tx-nr905. Primarily I use it to view virgin and PS3 as my bd player. FYI I'm hoping to purchase an Olive 03hd! I have a building at the bottom of my garden (approx. 15 mtrs away) which houses a workshop and Gymnasium. Although I have plans to exchange the gym to a cinema room in time, at present I would like to use the zone 2 or 3 of the onkyo to give me 'anything' down the gym??? I do not fully understand the possibilities that this could give me? If I was to only send audio signals to this area would I have to come back to the house to change the signal etc.????? As you can most probably understand, I feel that I own a quite respectable piece of kit but am not using it anywhere near its potential.

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