XXHighEnd

Ultimate Audio Playback => Playback Tweaks and Source related subjects => Topic started by: soundcheck on June 27, 2007, 12:27:09 pm



Title: Loudness War
Post by: soundcheck on June 27, 2007, 12:27:09 pm


You might want to check this one out!!! We discussed it earlier! ;)

http://en.wikipedia.org/wiki/Loudness_war

Cheers


Title: Re: Loudness War
Post by: PeterSt on June 29, 2007, 03:57:17 pm
Hi Klaus,

Somehow, a longer time ago, I already started reading that page. Now I finished it. Well, yep, such a shame.

What occured to me though, was this phrase :

Many digital music formats now have the ability to analyse the volume of a given piece of music and either store this as metadata to allow the player to compensate on playback, or to losslessly alter the music file to match the volume to a standard level.

This first part I was already thinking about, but which I must reject because of the "no DSP" principle. However, the second part indicates that the result would be "lossless", or IOW retains the (boosted) original when we'd go back to that. Of course it doesn't say lossless towards to the original as how it ever was (??), but I'd say this must be the intention of the message. If it *is* about the letter then :

This would imply that the "boosting" somehow lineairly was performed, which I cannot imagine (remember the intelligently cutoff JVC tracks ?).
Likewise, when all is clipped anyway, it's too late.

But what about this "lossless" ? would it be possible you think ? (first going to 24 bits or more is okay with me)

Peter


Title: Re: Loudness War
Post by: soundcheck on June 29, 2007, 06:43:22 pm
Peter.

Lossless calculations - e.g. when adding gain to the digital signal - are almost not achievable on most of the PC platforms. Rounding errors will cause losses.
You need to calculate in 64bit mode to get a reasonable small error and then you also need to add properly dither which is not that easy.

However, coming back to the digital volume control as a related topic - adding gain by using a DSP - and looking at the whole chain I still think ( actually I know it) a preamp will cause more trouble to the signal than a 64bit engine.

Cheers
Klaus