It's a noise for two reasons:A few years ago there was talk of a joint venture between Antonov and DASA of Germany, it seems to me that it was an attempt to market a westernized version of the Antonov An70 with Progress D-27 propfan engines, I think it produced a noise that caused some nausea, well it didn't prosper.
1. Germany (Airbus) already have comparable engine: TP400-D6 on A400M
2. To produce D-27 you'll need to replace all Russian parts and systems. D-27 was a joint project. I'm not sure that Ivchenko replaced them, considering Antonov considered An-70 variants with turbofan engines.
But I digress. I'm not sure if C-5M replacement is on the hill. This program will be expensive, signifiacntly so. While there are engines on the shelf that could make a plane of this size STOL, new airframe will be a long process.
Also, I'm not even sure who is to built them? Right now only 3 big companies left. Boeing, LM, and Northrop.