Jump to content

Replay Gain Controls


Angua

Recommended Posts

My first post so just a big thank you for a great app.

My question is about the controls within the Replay Gain section.  I think I understand the basics of Replay Gain i.e adding a tag to control the pre-amp settings of the player.  So what do the two sliders for RG Preamp / Preamp without RG actually do?

Thanks for your help

Link to comment
Share on other sites

By default as per the specs, ReplayGain is meant to adjust tracks so they all have the same maximum peak level of -14dB from digital maximum. This is achieved by either boosting low-volume-level recordings, or by reducing the volume of recordings that already peak at 100% (which is very common these days). This is done to allow plenty of headroom for post processing, EQ, effects, etc.

However that does result in the peak sound level - while still being equal between each track - being set somewhat lower than the device might otherwise be capable of. This can upset the "it goes up to 11!" brigade. :)

To compensate for this, there is a control which defines what level RG is meant to use as its desired peak level, and if you have low (or no) EQ boost settings then you can safely make that target level somewhat higher than the default would be. The "Preamp without RG" setting does the same thing for any tracks without any RG tags, and on the assumption that they probably peak at 100% it can reduce those tracks to match with the levels that RG tracks use, so hopefully they all sound similar.

Andre

Link to comment
Share on other sites

  • 2 years later...

Thread necro time!

I usually preamp, but with "Prevent clipping" - What if RG tags are set, but the peak level is not known? This is the case with Opus files, for some reason (there's some discussion about it). 

Would Poweramp take the risk and preamp +20 no matter what? 

Link to comment
Share on other sites

Andrew, I cannot help as for r128. This all (Opus vs. gain tags) goes well over my head. I recommend you to read Hydrogenaud.io OPUS subforum, there's a lot of lengthy discussions.

As for my question, I think PA just applies gain and leaves out the "prevent clipping" part. That's good. Because my first fear was, PAs implementation demands all tags (ie also peaks) in order to apply gain. "All or nothing".

Opus also has its own gain tags and IMO that means complexity. 5 people on earth understand opus/gain now. But I concluded I don't need to. Just apply gain, set preamps to 0. I use no postprocessing, so that's just fine.

EDIT: Andrew, from another thread I notived, opus headergain tags is a problem, so removing them via fb2k is still the way to go before using files in PA? ugh. If that were the case I might need to reconsider using apple lc aac again. EDIT2: I also noticed, removing Opus headergain in fb2k, then calculating replaygain again - also sets Opus Headergain values again. Seriously, this topic is a major PITA. Especially: You are never safe from players/applications applying those numerous tags in their own, creative way.

I so much wish PA one day could auto apply track/albumgain depending on playback order, just like fb2k can. Basically: random track order = trackgain, otherwise use album gain. 

I found something else. PA does not seem to process opus files with embedded CUESHEETS well. (Created by fb2k). Not displayed as multiple tracks and skipped at some point. 

Edited by Squeller
Link to comment
Share on other sites

46 minutes ago, Squeller said:

I so much wish PA one day could auto apply track/albumgain depending on playback order, just like fb2k can. Basically: random track order = trackgain, otherwise use album gain. 

There are future plans to update ReplayGain functionality, including for PA being able to scan music content and work out the required gain values for files that don't already have it embedded. OPUS is a law unto itself though, might be better to stick with more established formats if you can. As the saying goes, "that's the great thing about Standards, there are so many to choose from..."

Andre

Link to comment
Share on other sites

@Squellerare you really using very low bitates for music? That is where the real benefit that Opus seems to offer lies. But at anything 128kbps or higher, any benefit becomes debatable at best. Given the low rate of adoption, and the associated issues of getting things like Replaygain to work well, perhaps AAC is a better lossy solution for you? Or with cheaper storage solutions available, go lossless and use FLAC or ALAC?

Link to comment
Share on other sites

2 hours ago, MotleyG said:

@Squellerare you really using very low bitates for music? That is where the real benefit that Opus seems to offer lies. But at anything 128kbps or higher, any benefit becomes debatable at best. Given the low rate of adoption, and the associated issues of getting things like Replaygain to work well, perhaps AAC is a better lossy solution for you? Or with cheaper storage solutions available, go lossless and use FLAC or ALAC?

All my FLAC is mostly just a base for conversion to whatever target device.

Yes, AAC is also a great solution. But I would disagree OPUS usecase to be "really low bitrates". I've read numerous listening tests now and it seems to perform greatly in the realms of (close to) transparency, which starts somewhere.
Use case is here: Smartphone storage, storage size is a factor, but quality more so. output is Chromecast Audio. Bitrate (and accordingly filesize) target is somewhere at >180kbps, very safe spot for a modern codec.

But hey, I already decided to go for AAC@TVBR100. Opus is still a good alternative, because CCA does natively support it.

@andrewilleyhttps://xkcd.com/927/ Timeless.

Edited by Squeller
Link to comment
Share on other sites

1 hour ago, Squeller said:

Yes, AAC is also a great solution. But I would disagree OPUS use case to be "really low bitrates". I've read numerous listening tests now and it seems to perform greatly in the realms of (close to) transparency, which starts somewhere.
Use case is here: Smartphone storage, storage size is a factor, but quality more so. output is Chromecast Audio. Bitrate (and accordingly filesize) target is somewhere at >180kbps, very safe spot for a modern codec.

Any choice of format is a personal preference, and I am not suggesting any one of them should be proclaimed better than the others for this very reason. However since this is a lossy format we are discussing and there are other suitable ones that avoid the issue with Replaygain that you mentioned, it was worth bring up the alternatives as an option. In your case, since you have FLAC files available, that helps to ensure you can convert to whatever lossy format you want in the future, at any bit depth and sample rate you want.👍

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...