Arm mass for AS-309S is 3.5-4g without headshell.
The Ortofon 2M Black might be too compliant for this arm... If you use a really light headshell (6-7g or less) you might get away with it.
Not sure about the Shelter because the compliance ratings aren't easy to come by.
Bottom line, this is an arm best suited for the stiffer variety of moving coil cartridges, including SPUs. Cadenza and Kontrapunkt series should work fine here also.
Full disclosure, I work for the manufacturer. Just wanted to help!
The Ortofon 2M Black might be too compliant for this arm... If you use a really light headshell (6-7g or less) you might get away with it.
Not sure about the Shelter because the compliance ratings aren't easy to come by.
Bottom line, this is an arm best suited for the stiffer variety of moving coil cartridges, including SPUs. Cadenza and Kontrapunkt series should work fine here also.
Full disclosure, I work for the manufacturer. Just wanted to help!