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24/192 music downloads make no sense

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Re: 24/192 music downloads make no sense

#221

Post by lmm »

nullc wrote: post #181
lmm wrote: post #112

Earlier quoted context omitted.

Paper seems to be paywalled. I can't imagine any possible purpose for dithering before encoding that wouldn't be better served by dithering on playback.

At 16 bits dithering is probably pointless for listening purposes. What dithering does is it decorrelates the quantization noise with the signal. Absent it, quantization generates harmonic spurs. In theory, on a very clean and noiseless signal these harmonic spurs might be more audible than you'd expect from the overall quantization level. In practice, 16 bits is enough precision that these harmonics are inaudible ev…

The article is saying you can use dithering to represent sounds quieter than your 16-bit "0000000000000001". That's what I'm objecting to.

Re: 24/192 music downloads make no sense

#222

Post by sagawee »

hatsunearu wrote: post #10

The single worst thing that harms audio quality is excessive compression. It's ruining everything, I'd say. Heck, I'm sure everyone who knows their worth would agree that compression harms audio quality. Recommended reading: https://en.wikipedia.org/wiki/Loudness_war edit: compression as in dynamic range compression, not data compression like mp3 in audio

You are talking about (dynamic) compression applied to an entire song with the sole purpose of making it as loud as possible to the human ear but still complying to the max allowed peaks (or to the energy of the signal).

This does degrade the quality, sometimes heavily. Nevertheless it is done by mastering engineers (they rarely enjoy it) as well as by radio and tv stations extensively because of the psycho-acoustic fact that a songs appears to be better if it is played louder. This gives them an advantage over the competition: On average, people searching for a radio station are more likely to listen to your radio station if it is louder than the competition.

The main issue lies in the fact that the current peak measurement of audio signals does only marginally correlate with the perceived loudness and heavy compression is used to trick this system. The broadcasting industry is aware of this. An open and quite effective loudness measurement algorithm [0] has been introduced a few years ago and it gets slowly adapted all over the world by new broadcasting laws: AGCOM 219/09/CSP (Italy), ARIB TR-B32 (Japan), ATSC A/85 PRSS CALM Act (US), EBU R128 (Europe) and OP-59 (Australia). iTunes Soundcheck is also based on [0] and since this year Youtube applies this to newly uploaded videos as well [1]. Even games use [0] to keep their audio at a consistent loudness.

So slowly, the over-usage of compression does not give music producers and broadcasters any advantage anymore and beautiful dynamic music will be competitive again.

I have collected some links [2] about this topic. Because of the lack of any affordable implementation at the time I created one myself [3] with some additional notes [4].

[0] ITU-R BS.1770, http://www.itu.int/dms_pubrec/itu-r/rec/bs/R-REC-BS.1770-4-2... [1] http://productionadvice.co.uk/youtube-loudness/ [2] https://www.klangfreund.com/lufsmeter/manual/#about_loudness [3] https://github.com/klangfreund/LUFSMeter [4] https://github.com/klangfreund/LUFSMeter/tree/master/docs/de...

Re: 24/192 music downloads make no sense

#223

Post by StavrosK »

glitch wrote: post #198
StavrosK wrote: post #197

Everything else is fine and good in the article, but I can see the infrared in the Apple remote (and all the other IR remotes I've tried). It's faint, but plainly visible. Am I the only one?

Went to a dark room with an Apple Remote; let my eyes adjust for a little while. Pressed it many times; I couldn't see the infrared coming from the LED with my naked eye. (But the camera on my iPhone imaged the infrared from the remote's LED.) I envy your biological wavelength detection.

Hmm, that's odd. I've noticed this with lots of remotes, I usually just look at them to tell if the batteries are dead. I wonder why I can see it.

Re: 24/192 music downloads make no sense

#224

Post by Hello71 »

Franciscouzo wrote: post #165
Hello71 wrote: post #160

Earlier quoted context omitted.

no, because if you play at lower volume, that simply means that the quietest parts are closer to (or underneath) the threshold of hearing. I see it this way: let's say 16 bits is needed to represent the entire discernable dynamic range between the threshold of hearing and the threshold of pain. if you turn the volume to 50%, then you throw out 8 bits, but you also only need to represent 8 bits worth of hearing range.

turning the volume %50 down would yield 15 bits, not 8 bits, which would be discernible.

er, my log math is bad, but the point is still valid.

Re: 24/192 music downloads make no sense

#225

Post by chillingeffect »

w4 wrote: post #192
chillingeffect wrote: post #179

Earlier quoted context omitted.

I respect your opinion, but it's only your opinion, not a global truth. Compression is a style. There is far more to musicality and emotion than compression. The problem compression solves is that the environments where industrialized cultures now listen in are not dedicated listening areas, but alternately loud and quiet places, so compression makes all parts of the music almost equally loud so there are no drop out…

> bands and styles with wide dynamic range like the Pixies, Nirvana and dubstep One of these things is not like the others. I can't tell if you're trolling here, or if you legitimately don't know much about audio engineering, because Dubstep (and electronic music in general) is probably the most aggressively compressed and limited genre of music out there. If you actually do feel that Dubstep has a lot of dynamics, t…

heh no, sorry, I didn't meean to sound like i'm trolling -

it is extra-ironic, b/c yes dubstep uses compression a lot, but at the same time, a lot of the dubstep I've heard uses silence judiciously to create huge amounts of contrast - in between the speaker-shreddingly compressed passages.

Both house music and dnb IME tend to employ quiet as well to make the loud seem louder. It's mostly just rock and some americana these days on the radio that gets to me. Actually country is one of the most egregious genres, too. Sounds totally flat like AM radio.

Re: 24/192 music downloads make no sense

#226

Post by lips »

My third time reading this, and a new question popped into my head: Are there any volume adjustments (on software or hardware) that take into account the pain threshold curves? That is, volume adjustments that aren't flat, but that will attenuate the frequencies that will cause discomfort at the lowest volumes?

Re: 24/192 music downloads make no sense

#227

Post by the_d00d »

chillingeffect wrote: post #179
beat wrote: post #169

Earlier quoted context omitted.

I've played acoustic and electric instruments for over 30 years, and recorded numerous albums. Compression is the best tool we have for accurately reproducing the musicality and emotion of a musical performance. Without compression, most recordings would be unlistenable. Don't confuse the foolishness of the loudness wars for "compression is bad". That's like saying the internet is bad because there's porn on it.

I respect your opinion, but it's only your opinion, not a global truth. Compression is a style. There is far more to musicality and emotion than compression. The problem compression solves is that the environments where industrialized cultures now listen in are not dedicated listening areas, but alternately loud and quiet places, so compression makes all parts of the music almost equally loud so there are no drop out…

I have to admit that you might have some kind of point regarding FF, but they are one of the more tolerable mainstream bands. funny that you use two bands that Grohl was/is a part of as a counterpoint. It would almost be like me saying Starship is everything wrong with 80s hair bands and then saying that Jefferson Airplane is what music should be like. In reality, they are the same band and are a metaphor for the demise of the baby boomer 'locust' generation.

Re: 24/192 music downloads make no sense

#228

Post by cnvogel »

TheOtherHobbes wrote: post #134
ska wrote: post #55

Earlier quoted context omitted.

The article is pretty clear about this too - higher bitdepths and sampling rates can be quite useful in mixing and recording situations. They're pointless for playback.

No they're not. And no matter how many times this gets linked to on the Internet, it's still wrong. The basic problem: the quieter a sound or detail gets, the fewer bits of resolution are used to represent it. In 16-bit recording, there simply aren't enough bits to represent very low level details without distorting them with a subtle but audible crunchy digital halo of quantisation noise. In a 24-bit recording, ther…

""" in a studio, 0dB full-scale meter redline is calibrated to a standard voltage reference, and both consumer and professional audio has equivalent standard levels for the loudest level possible"""

This is only minor nitpicking, but the standard 0dB levels for professional audio (0dB reference at +4dBu == 1.23Vrms) and consumer audio (0dB reference at -10dBV == 0.32Vrms) are not meant to indicate the maximum ("loudest level possible") but just serve at a reference point, for e.g. the 1kHz sine you inject when setting up your gain throughout the signal chain. On most studio gear, you'll easily have +15dB headroom left.

AD/DA converters haven't really standardized on a full-scale level and there are quite a few different definitions in use: https://en.wikipedia.org/wiki/DBFS. Most "line level" ADC/DACs will have switches or jumpers to select between two or so settings. You'll choose them so that you are not likely to clip your ADC, and will only playback on your DAC with an appropriate level trimmed to not clip your analog gear.

Re: 24/192 music downloads make no sense

#230

Post by shmageggy »

ZoFreX wrote: post #194
shmageggy wrote: post #113

Earlier quoted context omitted.

Mastering for vinyl is very common in the industry. I don't have time to dig up a reference right now, but the medium has different constraints than digital so is usually mastered separately, especially for big budget stuff. The differing constraints are mainly that while CD has a hard amplitude limit (hence brickwall limiting), the constraint on vinyl is not hard in the same way -- it mostly has to do with amplitude…

I agree that mastering for vinyl happens, but you're not right about the dynamic range. CDs were popular initially because they have a wider dynamic range, the overly compressed / "loudness wars" tracks are nowhere near the limits of the medium. It is true that vinyl these days often has wider dynamic range - because the market for how songs sound is different for people buying vinyl, so they're mastered with wider r…

The comment was not about dynamic range, but the nature of the upper amplitude limit (hard vs soft/frequency dependent). That says nothing about the dynamic range, which is still a creative decision during mastering. I was trying to point out that vinyl mastering is common (contrary to parent post) and that one reason is the technical differences between mediums. I agree, though, that market pressures are a strong driver of the differing creative choices during mastering, but the decision to master separately for vinyl is often indepenent of that.
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