CD copies

Swampwalker is correct. Generally speaking, an SACD layer cannot be copied. The sole exception is that some early Playstation models could be used to create a decrypted ISO file or a DSD disc from the SACD layer.

An XRCD does not have an SACD layer. An XRCD has a redbook CD layer only. XRCD refers primarily to mastering process enhancements and may also include some manufacturing enhancements. In burning a copy of an XRCD, one would not be losing any mastering enhancements but one obviously would be losing any manufacturing enhancements.

An SHM CD may or may not have an SACD layer. SHM refers primarily to manufacturing and disc material enhancements and may also include some mastering process enhancements. In burning a copy of an SHM disc, an SACD layer if present could not be copied, only the redbook CD layer could be copied; however, although any mastering process enhancements would not be lost, the primary benefit of SHM which lies in manufacturing and material would be lost.

I cannot comment on Blu-spec.

Gz3827, since the CD/DVD burner is just copying digital files, could I make a CD copy of my hi-res computer files?

You can make a CD copy of hi-res audio files, but the copy you make will not be hi-res; rather, the copy will be 16 bit depth and 44100 Hz sample rate. All CDs (apart from SACD) are 16/44. Period. No other exceptions. So if you want to maintain the original high resolution on a disc that you burn, then you need to burn an audio DVD, not an audio CD. I've never done that myself so I don't know much about it, but it looks like Tom6897 pointed you in a good direction above.

got it. Thanks again, all.