Doug,
If you simply want to play YouTube on your system, a simple Bluetooth receiver, like the Auris BluME HD will do the trick. Simply play YouTube on your phone, laptop, etc., and connect that device to your system via the bluetooth connection.
You could purchase a DAC with a USB input and connect a USB cable from your iMac to the DAC and a set of RCA interconnect cables from the DAC to your system. Anything you play on the iMac can be output to the DAC via the USB connection and you'll hear the sound on your system, instead of through the speakers on your iMac.
For better sound than Bluetooth and YouTube can provide, a streamer, like the BlueSound Node 2i will allow you to stream nearly unlimited content from a subscription streaming service such as Qobuz, Tidal, Amazon HD, Spotify, etc. It also has a built-in bluetooth receiver, so you could also stream YouTube to it. It also streams internet radio stations, such as Radio Paradise, etc. Lastly, streaming high-res content via Tidal or Qobuz will offer significantly better sound quality than streaming YouTube or Spotify over bluetooth connection.
You have many choices. Good Luck. I hope you find what you need and get music back into your life.
If you simply want to play YouTube on your system, a simple Bluetooth receiver, like the Auris BluME HD will do the trick. Simply play YouTube on your phone, laptop, etc., and connect that device to your system via the bluetooth connection.
You could purchase a DAC with a USB input and connect a USB cable from your iMac to the DAC and a set of RCA interconnect cables from the DAC to your system. Anything you play on the iMac can be output to the DAC via the USB connection and you'll hear the sound on your system, instead of through the speakers on your iMac.
For better sound than Bluetooth and YouTube can provide, a streamer, like the BlueSound Node 2i will allow you to stream nearly unlimited content from a subscription streaming service such as Qobuz, Tidal, Amazon HD, Spotify, etc. It also has a built-in bluetooth receiver, so you could also stream YouTube to it. It also streams internet radio stations, such as Radio Paradise, etc. Lastly, streaming high-res content via Tidal or Qobuz will offer significantly better sound quality than streaming YouTube or Spotify over bluetooth connection.
You have many choices. Good Luck. I hope you find what you need and get music back into your life.