Streaming Youtube from sources such as Roku, Amazon FireTV, AppleTV uses a really crappy youtube app and sound quality (as well as video quality) will be pretty bad.
Streaming using the web browser on the actual iMac computer always gives superior audio/video quality. It will also allow you to force the youtube resolution to a higher rate (such as 1080p or 720p). These higher rate videos always have better sound data than the 480p setting.
Like others have suggested, your best bet is to get a USB DAC and connect it directly to your iMac.
Streaming using the web browser on the actual iMac computer always gives superior audio/video quality. It will also allow you to force the youtube resolution to a higher rate (such as 1080p or 720p). These higher rate videos always have better sound data than the 480p setting.
Like others have suggested, your best bet is to get a USB DAC and connect it directly to your iMac.