I mean why would you want to have 4 separate channels being processed by 1 machine? Unless you're trying to budget a streaming house? Now if you wanted to converged 4 channels into 1 that's a different story completely, and while demanding wouldn't require anything more than an i5 dedicated to it.
Think of streaming more like television channels, all the shows have their own cameras, microphones, and equipment, that they then send to the master. The master being the actual channel you're watching. In the event of running multiple channels, with completely different content you'd want separate hardware. There is no optimal reasoning to run various channels w/ varying content between each channel other than what is honestly greed, and in this situation you'd only degrade quality of each channel by not dedicating its own hardware to it.
Duplicating a single channel to several locations is nothing.