clipping Limit vs Smooth Equalizer/ Tone Gains

[PaperBoat]

"Limit" vs "Smooth Equalizer/ Tone Gains", what's the difference?

[Xander71]

Smooth Equalizer / Tone gains reduce output gain automatically according to volume, while limiter is always active if it's on. Both works for the same purpose, to prevent clipping which results in nasty digital distortion. 

[andrewilley]

The Limiter is a pretty simple tool which checks to see if the signal is in danger of exceeding 100% digital maximum, usually as a result of EQ adjustments, and instead of changing the EQ adjustments it simply attenuates the whole signal for a short time to avoid oversaturation and clipping distortion. It's not as subtle as a Normalise feature though, so you may notice volume dips, especially during heavy bass sections of your music for example.

A better solution is not to work so close to the maximum in the first place, and if you want to apply heavier EQ/Tone boosts, also turn the overall gain down a bit to compensate. The spec for ReplayGain does this by the way, its default recommendation is to actually set a target peak volume of -14dB from maximum to allow ample processing headroom (although PA does not go quite that far).

Andre

[PaperBoat]

@andrewilley  @andrewilley

Edited July 25, 2022 by PaperBoat
irresponsive forum.

[andrewilley]

@PaperBoat For a better understanding of ReplayGain, see the wiki entry: https://en.wikipedia.org/wiki/ReplayGain

Basically, ReplayGain is a pre-saved value, inserted as a metadata tag within an audio file, which lets player software know the maximum volume level that will be found within that audio file.

For album tracks, there is also a second saved value which contains the maximum peak level for any tracks within the current album. This second value will remain the same for every file in one album, whereas Track RG levels will vary file by file. So for example a classical recording, where one movement/track is intended to be much quieter than another more bombastic piece, will retain the same relative volumes rather than the quieter track being boosted to become as loud as the bombastic piece. 

Player software (Poweramp in this case) then uses the ReplayGain tag to adjust the gain for each file (either by increasing or decreasing the level) so that the maximum peak level reaches a given value set by the user or software. That way the maximum volume of everything you listen to should sound about the same, regardless of how loud or quiet the original recording might have been. Note: the level is not adjusted 'on the fly' (that would require a feature called Normalisation, or Automatic Gain Control) but the same boost or attenuation is applied to the whole of each track.

The RG spec suggests that target level should be 14dB below 100% digital maximum, to allow plenty of headroom for EQ and other downstream adjustments, but PA doesn't seem to go that far - I assume partly because DVC makes distortion much less likely. If you don't use any heavy EQ/Tones boosts (especially bass) then you can push that level up a bit if you find the default settings a bit quiet. Use Settings=>Audio=>Replay Gain=>RG Preamp. There is also another knob to adjust the gain applied to any tracks that don't contain any RG data - which may well be 100% recordings, so could sound louder than the target level for your other songs.

After some testing with my own files (at mostly flat EQ) I settled on +6dB for the RG Preamp and -2.4dB for the non-RG Preamp, but your needs may vary. I also use Track Gain, as I mostly listen to individual songs rather than full concept/concert/classical albums which benefit the most from Album RG. There is an existing Feature Request to be able to automate that option by the way, so Album RG could be applied automatically to album listening, while Track RG would be applied to Folders, All Songs, Shuffled play, etc.

Andre

[PaperBoat]

@andrewilley Thanks 😊