I have an dead ART Legato SPDIF convertor that I just loved. Unfortunately I can't get a hold of the small manufacturer for service. He disapeared and stopped responding about the beginning of covid... so who knows?
I liked it because it was designed from the ground up to pass a very low jitter low- rez, non-upsampled signal with a very well though out power supply.
I cant find another unit like it. I'm using a cheapo Douk Audio which seems to be universally liked on the intraweb. I think it's OK for now but would like to find a Legato knock off.
I'm not sold on the ABBAS SPDIF units. Do things really need tubes? Looks too complicated as well.