I have just purchased my first albums in HiRes.

I have noticed that in both my HiFi system (NAD C368 with BlueOs module connected to a NAS) and in the car sound system (VW Discover Pro compatible with HiRes FLAC through SD cards or HDD connected to any of the USB plugs available), this new albums sound considerable louder than the FLAC files ripped from my CD collection. My questions are:
- Is there a way to apply loudness normalization to the HiRes FLAC files?
- I am in the process of ripping my entire CD collection and I am not sure which DSP I should choose between Replay Gain (track) or EBU R128. What are the benefits of each and the ideal choice considering my HIFi and car systems?

Thank you in advance for your help.

Have a great day.