I used those all the time back in the day, had 3 set up and running at once and streaming music from any app to any device with Airfoil. one of them was a Rev. A and I found a special version of AirPort Utility that got around the block to run on newer macOS.
that was years ago but there may be something similar now!
definitely worth a thorough Google Search. that's how I found it!
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