Comparing SACD sound to High Res

Gammajo,
Not quite. Not all sacd's are recorded/mastered/remastered at optimal quality. This also applies to cd's and hi-res files, whether pcm or dsd. The final sound quality of any format depends on the quality of the whole production process. So, well-produced cd's can trump poorly produced sacd's/hi-res pcm or dsd files. That said, if all things are equal in the production process in terms of quality, generally sacd's should sound better than cd's but if compared to hi-res pcm files, the jury is still out. It all boils down to a matter of taste, or listening with our own ears.
So,how do we know the sq before we buy? Reading music reviews help a lot. Recommendations from music forums like the one here in A'gon are very helpful too.
Happy hunting and happy listening! J.

Jon2020, I believe that's what Gammajo said here:

...SACD can hold its own with all the new high res download formats, making the performance and recording quality more of a factor in hearing stellar, engaging sound than what high res format it is in.

Tomcy6,
I agree with what Gammayo said but to complete the whole picture, SACD is 64dsd. Hi-res can be run up to 384/24(DXD) or 256dsd.
I have heard good quality hi-res pcm 192/24 and 128dsd trump good quality SACD's, again with all things equal.
As always, the proof is in the listening with one's own ears and in the context of one's own system.
Cheers! J.

Thank you everyone for the input. In my system I notice a big difference in well recorded CDs, for example Reference Recordings HDCD and run of the mill on my Ayon CD5s player.

I have listened to a few DVD-A and SACD but only over my Sony DVD player (though the same preamp, DAC and speakers) and am wondering about investing in a better SACD player - any of the used ones now available on A'gon highly recommended to give SACD a fair trial?

Gammajo,
Have a look at the Ayre C-5 listed here. Going by the great pics of its condition and the rave reviews so far, this may just be what you are looking for. Just to qualify, I do not know the seller.
Happy hunting! J.