Does Replaygain (or Sound Check) Work on ALACs?

[freddy33]

I'm running Rockbox v3.13 on an iPod 3G updated with a 1300mah battery & 80gig Toshiba drive & was unable to locate an answer for this...

In Apple mode, Sound Check works fine on normalizing the volume of everything, but, in Rockbox, Replaygain normalization only works on mp3s--all of my ALACs (16/44 or 24/48 - converted from CDs with the current version of dbpoweramp) play at widely varying volume levels.

I've been through the Replaygain settings, but didn't see anything that references file format. I've also been through the Sound & Playback settings and didn't see anything there either.

[saratoga]

Yeah it does:

http://download.rockbox.org/daily/manual/rockbox-ipod3g/rockbox-buildap2.html#x17-330000B

[freddy33]

Thanks (again!), saratoga for the quick response. I know ALACs are supported, but I don't understand why Replaygain isn't working on them (when Apple's Sound Check does work) or how I can get it to work?

[saratoga]

Do you have replaygain tags on your files?

[freddy33]

No, but I wouldn't think that's the issue since the problem's limited to just the ALACs. 9/10's of the files on the 'Pod are mp3s, which Rockbox normalizes perfectly; it's just the ALACs, which were Sound Checked at the same time as the mp3s.

What I'm asking is whether ALACs require something different than mp3s for normalization in Rockbox?

[saratoga]

Replaygain absolutely will not work without replaygain tags.  So i guess you're basically asking if soundcheck values stored in MP4 tags are used if its missing.  I have no idea, but I tend to doubt it. 

[freddy33]

Okay, that's the answer I needed (tho' not the answer I wanted to hear).

Do you know if the Replaygain tagging affect/remove the existing Sound Check tagging? I'd hate to mess up the existing normalization that's working on all the mp3s..

[saratoga]

Unless it deletes your existing tags it won't have any effect on the SoundCheck values. 

[saratoga]

Actually I'm curious how these tags look.  Could you post a link to an AAC or other MP4 based file with soundcheck tags?

[freddy33]

PM sent.

[freddy33]

saratoga, I need to free space on the server, so I'm removing the file I posted for you at the end of the day. Hopefully, you've already downloaded and evaluated it. Thanks.

[saratoga]

Yeah I got a copy, didn't get a chance to look at it though.