Members rasputin1963 Posted July 19, 2012 Members Share Posted July 19, 2012 I'm running some CHESKY recordings, known for their extremely high attention to audio quality in every measurable way, through various spectrometers and visualizers. CHESKY recordings rather "set the bar" for how auditorily perfect and aesthetically beautiful a digital recording can be. I am surprised to see that a number of these pieces peak out at -22dB... With an actual average at about -24dB Wow. It would never have occurred to me to record and normalize at that quiet a dB level. I do understand the "loudness wars" and the need for greater dynamic variety in digital recordings, but.... gee. Maybe I'm just a rock 'n' roll baby who's forgotten how subtle and dynamically delicate a record should be... Is this YOUR own practice, too? Why or why not? Link to comment Share on other sites More sharing options...
Members A. Einstein Posted July 19, 2012 Members Share Posted July 19, 2012 The loudness is relative to the type of music on a disc. On a disc with only romantic works where the music stays in the piano/mezzo piano range and never reaches a forte, then a peak of about -20 dBFS is the prefered signal loudness. On a disc where a symphony reaches forte fotissimo, then the peak can be 0 DBFS, ot a tiny bit less, for example -1 dBFS. And when both works, piano/pianissimo works and forte fortissimo reaching works are on the same disc, the same signal loudness applies. If that would have not been done that way, then the dynamic and loudness impression of the listeners would make not dynamic sense over the full disc. Link to comment Share on other sites More sharing options...
CMS Author MikeRivers Posted July 19, 2012 CMS Author Share Posted July 19, 2012 Nothing wrong with leaving plenty of headroom. Most people are too get up and turn up the volume if they want it louder, or think that there must be something wrong if it sounds too quiet. Link to comment Share on other sites More sharing options...
Members philbo Posted July 19, 2012 Members Share Posted July 19, 2012 Are you sure this is Peak (and not RMS)? For uncompressed acoustic instruments, an RMS of -24 to -22 dBFS is about right; it leaves the peak levels about 1 or 2 dB below clipping. If it's the Peak level, it would depend on the medium. It would be fine for audio from a DVD , but for a would provide a lot of quantization distortion for any quiet passages on a CD. Link to comment Share on other sites More sharing options...
Members A. Einstein Posted July 19, 2012 Members Share Posted July 19, 2012 a relative low loudnees usually sound way better then the pumped up stuff, or music which was recorded with a limiter in the first place apart from that an un-altered symphony recording on a CD has passages where the loudness drops down to -44 to -50 dBFS Peak at the ppp parts, this is of course music you don't listen in a car Link to comment Share on other sites More sharing options...
Members JeffLearman Posted July 19, 2012 Members Share Posted July 19, 2012 Are you sure this is Peak (and not RMS)? For uncompressed acoustic instruments, an RMS of -24 to -22 dBFS is about right; it leaves the peak levels about 1 or 2 dB below clipping.If it's the Peak level, it would depend on the medium. It would be fine for audio from a DVD , but for a would provide a lot of quantization distortion for any quiet passages on a CD.That's what I was thinking too. Peaking at -22 flat scale would be odd, unless the material was sooo even that it worked out to the right perceived loudness to fit with their other tracks. If you peak at -24 dBFS, you're wasting 4 bits of the medium. With 24-bit audio, that leaves 20 bits which is really plenty. But in 16-bit formats, you're down to 12, which isn't so great. Welcome back, pupster. I agree with what you said, too, though I didn't check your math. ;-) Link to comment Share on other sites More sharing options...
Members A. Einstein Posted July 19, 2012 Members Share Posted July 19, 2012 that would mean that all recorded classical music would have a sonic quality problem during the pianissimo passages Link to comment Share on other sites More sharing options...
CMS Author MikeRivers Posted July 19, 2012 CMS Author Share Posted July 19, 2012 A peak-to-RMS ratio of 2 dB is really pretty odd for a Chesky recording. A really small ratio is what makes recordings able to sound loud. That's about how pop records are mastered these days. A difference of 10 dB is usually good enough to hear dynamics and still not lose quite parts to ambient noise. I would believe an eyeball average of peaks at -22 dBFS or so. Surely there are some that go above that, but perhaps just for a few samples. There aren't any really good ways of calculating RMS for music (or noise, for that matter) but there are a number of programs that try. When needed, I'll quote the figure that Sound Forge gives me, but I'll always say that it's Sound Forge's calculation. Peak level, however is easy to observe on any DAW waveform graphic, and that's what you don't want to spend too much time too close to full scale (0 dBFS). Link to comment Share on other sites More sharing options...
Members blue2blue Posted July 19, 2012 Members Share Posted July 19, 2012 What learjeff and philbo said. An actual peak that low -- on a 16 bit CD would, I would think be 'too much of a good thing.' (Headroom.) But depending on the program material, an RMS average that low might well be appropriate. (Of course, when this thread is next to the Skrillex thread, you're gonna hear a lot of Skrillex comin' through the walls -- with his -6 dB RMS notched tube tracks.) And, of course, Albert is right, the more dynamic mix will usually sound better than a squashed mix when they're both turned to the same effective listening level. Because it will still have dynamics. Just like real music. EDIT: And Mike, whose post hadn't shown yet when I started, has an excellent point about the ratio of peak to average being a rough indicator of relative dynamic impact. Link to comment Share on other sites More sharing options...
Members A. Einstein Posted July 19, 2012 Members Share Posted July 19, 2012 Since about 2 years we measure program material with the new meter standard, with which we can pretty much be exactly within the different delivery standards Link to comment Share on other sites More sharing options...
Members JeffLearman Posted July 19, 2012 Members Share Posted July 19, 2012 (Of course, when this thread is next to the Skrillex thread, you're gonna hear a lot of Skrillex comin' through the walls -- with his -6 dB RMS notched tube tracks.) Crosstalk! I thought that was a thing of the past! A -- what "new meter standard"? Thanks Link to comment Share on other sites More sharing options...
Members JeffLearman Posted July 19, 2012 Members Share Posted July 19, 2012 that would mean that all recorded classical music would have a sonic quality problem during the pianissimo passagesPianissimo sections are probably fine with only 12 bits. By their nature, they're the quietest sections of the work. And yes, the noise floor is higher there. I'm sure you can do the math, but for everyone else's sake, it's roughly 6 * 12 = 72dB. Now, that was pretty darn good back in the days of analog tape, but for analog tape, the noise down there was fairly white, whereas quantization noise is significantly more annoying and noticeable at the same dB level. This (as I'm sure you know) is why we use dithering. Of course, dithering turns the bottom bit or half-bit into noise, so now we're down to 66 dB S/N ratio, give or take. Good enough for my ears, but certainly not stellar. I did a fair bit of work with 12-bit audio, years ago. The most noticeable bad effect is tails, when music fades to silence: you can very clearly hear the quantization noise at the end, even with my far less than golden ears. For a quiet passage, with little dynamics, we're fine. The OP wasn't talking about a quiet passage, but the whole piece. We certainly don't want to do audio in 12-bit format, and peaking at -24dBFS for a whole piece, when the underlying format is 16-bit, is exactly that: a 12-bit recording. BTW, I'm talking about peak levels in this post here, not RMS. Link to comment Share on other sites More sharing options...
Members A. Einstein Posted July 19, 2012 Members Share Posted July 19, 2012 A -- what "new meter standard"? Thanks EBU R128 http://tech.ebu.ch/docs/r/r128.pdf For example this metering software VisLM-H: Link to comment Share on other sites More sharing options...
Members blue2blue Posted July 19, 2012 Members Share Posted July 19, 2012 Interesting. More on EBU R128 -- but with links... http://tech.ebu.ch/loudness/ Link to comment Share on other sites More sharing options...
CMS Author MikeRivers Posted July 19, 2012 CMS Author Share Posted July 19, 2012 Interesting. More on EBU R128 This is a standard for loudness uniformity, not SPL at the eardrum. It's not about how loud a concert is, it's about how much louder the commercials are than the program you're watching on TV. Link to comment Share on other sites More sharing options...
Members blue2blue Posted July 19, 2012 Members Share Posted July 19, 2012 This is a standard for loudness uniformity, not SPL at the eardrum. It's not about how loud a concert is, it's about how much louder the commercials are than the program you're watching on TV.Right. I think that's what most of us are concerned with in this thread: relative loudness of program material from source to source. Link to comment Share on other sites More sharing options...
Members A. Einstein Posted July 20, 2012 Members Share Posted July 20, 2012 Today the production agreement contain the technical audio requirements in R128 values. The EBU R128 levels and measurement are compliant to International Telecommunication Union's ITU-R BS. 1770/1, and US Advanced Television Systems Committee (ATSC) ATSC A/85. Clients which have not updated the delivery specs to R128 yet, are still in the old audio levels and measurement (loudness or volume) format PPM. See page 10:http://www.channel4.com/media/documents/commissioning/PROGRAMME%20MANAGEMENT/TechnicalStandards.pdf Link to comment Share on other sites More sharing options...
Members JeffLearman Posted July 20, 2012 Members Share Posted July 20, 2012 Thanks! Link to comment Share on other sites More sharing options...
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