CD >> FLAC>> MP3. Is replaygain DSP needed at each step or just the once?

[m4rk]

Hi,

I am about to batch convert my FLAC files to MP3. The FLAC files already have replaygain tags. For the batch convert do I need to reapply the replaygain dsp when converting to mp3 or are the FLAC replaygain tags carried across correctly to the converted mp3's automatically?

I think the answer is that have I do have to use replaygain twice. Once from CD to flac and then again from FLAC to MP3. I just wanted to be sure before I convert my entire collection. Can someone please confirm this. Thanks Mark


edit ......

Just did a test conversion with replaygain applied to my FLAC files and found that the gain values are the same for both FLAC and the converted MP3's. If I do not use RG a second time when going from FLAC to MP3 then the gain tags in the MP3 are empty.

So I think I have the answer.. I do need RG at both stages.

I still would like a confirmation that I have it correct. Thanks Mark

[garym]

Re: CD >> FLAC>> MP3. Is replaygain DSP needed at each step or just the once?

There may be an option to carry over these tag values but I prefer to redo the RG tags on conversion. Values are a bit different.

[m4rk]

Re: CD >> FLAC>> MP3. Is replaygain DSP needed at each step or just the once?

Just checked again and FLAC gains and peaks are same as mp3 gains and peaks



Test - - - dBPoweramp batch convert from FLAC's with existing replaygain tags.

1st file is MP3 with replaygain reapplied in batch conversion.
2nd file is FLAC source file with existing replaygian tags
3rd file is MP3 without replaygain applied in conversion... FLAC replaygain tags are not carried over to the mp3

note : all FLAC and MP3 replaygain values are identical.

Album was Adele 19.

........edit after a bit more testing

I have run into a problem. Album gain is not calculated if I add another DSP action to the batch convert. I added Folder.jpg preserve to copy folder.jpg and a txt file into the mp3 destination folder. Now I am not sure what I should do to get folder.jpg copied and have RG album gain calculated. Maybe re-run batch convert a second time and just RG only after the initial mp3 conversion and file copy?????

I did a test of this sceneraio too. The replaygain for some tracks were slightly different but just by 0.01. Rounding errors?

[garym]

Re: CD >> FLAC>> MP3. Is replaygain DSP needed at each step or just the once?

Hmmm, my recollection is that using the RG DSP in conversion from FLAC to mp3 did create both track and album RG values. Are you sure that when you added the RG DSP you checked the option to add both track and album values.

But given that these values are virtually the same, maybe just allow values from flav to carry over. RG is not exactly an exact science at the decimal point level.