Hey,
Roon core is CPU intensive, but that's relative. If you don't use any DSP, especially upsampling to DSD, or convolution filters it doesn't need that much CPU power. It may also compete for RAM, which browser pages can really eat up, which competes with Roon. If you run out of RAM, you end up doing a lot of paging out to and from disk, and that brings the performance of everything to a crawl.
Putting your Roon core on a dedicated NUC means you won't be making it compete for resources on your iMAC.
Roon core is CPU intensive, but that's relative. If you don't use any DSP, especially upsampling to DSD, or convolution filters it doesn't need that much CPU power. It may also compete for RAM, which browser pages can really eat up, which competes with Roon. If you run out of RAM, you end up doing a lot of paging out to and from disk, and that brings the performance of everything to a crawl.
Putting your Roon core on a dedicated NUC means you won't be making it compete for resources on your iMAC.