I am currently in the early process of re-ripping my audio CD collection with dBpoweramp using the settings recommended by dBpoweramp's manual. The collection will take around a month to re-rip. Out of curiosity (and possibly a cautionary measure to avoid having to re-rip my entire collection again), I have some audio property questions that I would like to ask. I am re-ripping my CDs to FLAC. I want the FLAC files to have the same audio quality as that on the CDs. I am aware that the audio quality and properties of songs on CDs may be different due to factors such as how and when the songs were recorded in the studios and when the CDs were manufactured. Like I said, I am trying to get the same audio quality from the CDs copied into FLAC files. I have looked at the standard properties for audio on CDs. I am also using an audio analyzer called "Fakin' the Funk?" to check if the songs that I have ripped to FLAC so far are real, fake, or corrupted. So far, they all look good. My intention is to have every song recorded to FLAC with a possible copy and conversion process to MP3 after the CDs are ripped and verified. My questions are:

1. Which audio properties in the FLAC Files should be identical?
2. Which audio properties in the FLAC Files should be different?

Here is the information that my audio analyzer has provided of the CDs that I have copied so far:

FLAC Audio Properties
Identical:
• Channel Mode: Stereo
• Bits Per Sample: 16
• Sample Rate: 44100
Differing:
• Bitrate: 451-968
• File Size (Due to track duration and type of song)
• Frequency: 21619-21878 (Some albums have different track frequencies while other albums have track frequencies that are identical)
• ReplayGain (Track): -7.4800 to -6.8500 [with variations of + and – levels on list (Not using ReplayGain Album))]

Thanks