Is 'prevent clipping' needed?

[DefineByte]

If I use foobar2000 to apply ReplayGain (with 'prevent clipping' set in the scanner) do I still need to enable 'prevent clipping' in Rockbox to ensure music won't clip?

The only gain I'm applying in Rockbox is -2dB in the ReplayGain pre-amp, as I read this should ensure that crossfeed doesn't clip. No other DSP processing is being used.

[bluebrother]

ReplayGain only lowers the volume. I don't know how ReplayGain works internally but from my understanding the "prevent clipping" setting is not needed -- I'm using ReplayGain since it was added and never enabled the "prevent clipping" setting. Never had the impression that the music clipped.

[Lear]

If I use foobar2000 to apply ReplayGain (with 'prevent clipping' set in the scanner) do I still need to enable 'prevent clipping' in Rockbox to ensure music won't clip?

Scanning doesn't prevent anything. So yes, to get the "Prevent clipping" functionality, it needs to be enabled in Rockbox.

The only gain I'm applying in Rockbox is -2dB in the ReplayGain pre-amp, as I read this should ensure that crossfeed doesn't clip. No other DSP processing is being used.

That won't help much, as the preamp is only used if ReplayGain is being applied. You could use the equalizer pre-cut instead (and set the gain to zero for all bands).

Doubt it would be needed for the Crossfeed though. Relax and enjoy the music instead.

ReplayGain only lowers the volume. I don't know how ReplayGain works internally but from my understanding the "prevent clipping" setting is not needed -- I'm using ReplayGain since it was added and never enabled the "prevent clipping" setting. Never had the impression that the music clipped.

ReplayGain can raise the volume too, though that doesn't happen very often.

What "Prevent clipping" does is that it takes the peak volume (which is calculated during the ReplayGain scan) and if needed, lower the volume so that no clipping occurs.

[bluebrother]

ReplayGain can raise the volume too, though that doesn't happen very often.

Oh, really? Wasn't aware of that, good to know

[DefineByte]

Hmm, maybe I'm not being clear. I am applying ReplayGain.

What "Prevent clipping" does is that it takes the peak volume (which is calculated during the ReplayGain scan) and if needed, lower the volume so that no clipping occurs.

It's my understanding that Foobar2000 does this at the scanning stage. It will check the peak and lower the volume below the  target dB if needed (when the option is selected). I just wanted to know if that should be enough to prevent clipping in Rockbox.

I think it was the guy that wrote it who said the bass could clip with crossfeed enabled and that a -2dB gain was a good idea. I may be mistaken of course.

[Lear]

Hmm, maybe I'm not being clear. I am applying ReplayGain.

"Applying" as in "Scanning with Foobar2000" or as in "Enabling ReplayGain in Rockbox"? Oh well, doesn't really matter, as long as you know that ReplayGain must be enabled in Rockbox for the pre-amp to be applied (and then only for files with ReplayGain information).

It's my understanding that Foobar2000 does this at the scanning stage. It will check the peak and lower the volume below the  target dB if needed (when the option is selected). I just wanted to know if that should be enough to prevent clipping in Rockbox.

I very much doubt Foobar does that. According to the ReplayGain spec, that is something that should be done during playback, so that the user playing the file can decide if it should be done or not.

Also, if it was done during scanning, why would Foobar have the playback setting "apply gain and prevent clipping according to peak"?

[DefineByte]

Argh, somebody shoot me. I forgot which section of foobar's options 'prevent clipping' was in. It is indeed in playback.  

Well that was a thread worth making.  xD :hides: