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Loudness Penalty: Find out if audio will be turned down by streaming services

loudnesspenalty.com

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Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#31

Post by viraptor »

QasimK wrote: post #26
ggg9990 wrote: post #22

Earlier quoted context omitted.

The free tier is to get paid users. If you have no chance of being paid, Spotify hardly cares whether you stay or go.

I’m sure Spotify would rather everyone that isn’t going to pay use their free product than move to competitor X.

Pros: they potentially play the Spotify ad to their friends, effectively advertising the service.

Cons: each playback means bandwidth + royalties cost.

So the question is, does the probability times the return from their friends bring more money than the free playbacks? I'd really like to know the answer.

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#32

Post by wl »

jtbayly wrote: post #15
amelius wrote: post #11

Why do audio formats use a linear scale, instead of exponential (like our ears seems to use)?

I'm not sure what you are referring to with audio "formats," but audio programs work in dB, which is logarithmic.

Audio is commonly represented in a format called pulse code modulation (PCM), where the amplitude of the sound is recorded using an integer or a floating point number (a "sample") anywhere from 12,000 to 192,000 times a second. Each sample is usually linearly proportional to amplitude rather than logarithmically.

I am unaware of any audio program which internally represents audio in dB. Waveform displays default to linear scales, though logarithmic scaling is usually available. Just about the only place where logarithmic scales are the default is frequency domain graphical representations like spectrograms.

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#34

Post by quzyp »

hamburglar wrote: post #16

Ironic that Spotify will apparently penalize the music for being "too loud" when their ads are regularly ear-splittingly loud. It's egregious. When listening with earbuds, I have to have a quick reaction on the volume control because the commercials literally hurt my ears.

That's due to their cutting-edge recording technology: https://youtu.be/BvQ571eAOZE

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#35

Post by namibj »

wl wrote: post #32
jtbayly wrote: post #15

Earlier quoted context omitted.

I'm not sure what you are referring to with audio "formats," but audio programs work in dB, which is logarithmic.

Audio is commonly represented in a format called pulse code modulation (PCM), where the amplitude of the sound is recorded using an integer or a floating point number (a "sample") anywhere from 12,000 to 192,000 times a second. Each sample is usually linearly proportional to amplitude rather than logarithmically. I am unaware of any audio program which internally represents audio in dB. Waveform displays default to l…

Actually 32bit float is such a logarithmic format.

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#36

Post by wanderfowl »

amelius wrote: post #11

Why do audio formats use a linear scale, instead of exponential (like our ears seems to use)?

Variations in pressure, which form the basis of sound, are linear, and thus, are measured in a linear unit (Pascal, Pa ). These (or a similar unit derived from electrical changes associated with pressure changes near a mic) are what are used for sound capture. It's awkward because we're dealing with a range from ~20 Micropascal to 100,000,000+ Micropascal in the world.

Rescaling to dB, a logarithmic unit, both better mirrors how humans hear, and brings the numbers under control, 0-135dB is nicer.

But at least for me, I like capturing and storing in a Pascal-ish unit, because I'd rather capture pressure linearly and convert to human-interpretable log units where needed. If nothing else, because things like waveform addition are a bit more straightforward mentally on linear scales. Folks have made other decisions in some formats, but I've never found it compelling.

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#37

Post by nkozyra »

stephengillie wrote: post #33

Wasn't YouTube supposed to do this a few years ago?[0] Yet some videos at full volume are still quieter than other videos at 10% volume. Does it not work? [0] http://productionadvice.co.uk/youtube-loudness/

This is about automatic volume reduction, not normalization. In other words, YouTube isn't going to adjust your volume up, only down if it's too loud (or saturated?)

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#38

Post by janwh »

kstenerud wrote: post #30
janwh wrote: post #27

Interesting idea, but personally I like the Dynamic Range (DR) measurement developed by the Pleasurize Music Foundation more. It also provides a one-value output that has a direct relation to the statistics of the input audio, and AFAIK it is a somewhat established measurand in audio engineering. Self-plug: A while back I reverse-engineered the DR algorithm and implemented it as a Python script. It's [DRmeter on GitH…

Is that similar to what replaygain uses for adjusting loudness?

TIL of ReplayGain, thanks!

From what I quickly gathered from the specs^1, Replay Gain (RG) and Dymanic Range (DR) are indeed similar in the grand scheme of things. Both algorithms employ percentile-based statistic of RMS values. While RG is determined by the 95% percentile of RMS values on 50ms audio frames, DR uses the 80% percentile on 3-second-long audio frame RMS values. So RG is definitely on the side of short-term analysis, while DR is long-term.

What differentiates RG more plainly though is its stronger psycho-acoustical foundation in regards to frequency response: It applies a so-called "Loudness filter" (modelled after the Equal-Loudness contour^2 found in human hearing) before doing the RMS statistics. The Equal-Loudness contour (also known as "Isophone" where I come from) is in turn modelled after non-linear response of the ear to sound pressure levels in relation to the frequency. It basically adjusts for what in layman's terms I'd call "Importance" of the different ranges.

Therefore I'd say RG is very much focused on what human hearing will perceive as loud (too loud, or just loud enough), while DR focuses on "exposing offenders in all ranges of the spectrum". My educated guess would be: Loud bassy sounds would not harm an RG score, while having a significant impact on the DR, as its not attenuating low frequencies.

Would be interesting to see a comparison of the two!

[1]: http://wiki.hydrogenaud.io/index.php?title=ReplayGain_specif...

[2]: https://en.wikipedia.org/wiki/Equal-loudness_contour

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#39

Post by dahauns »

mortenjorck wrote: post #8
rcthompson wrote: post #2

I'm confused about why this website is using the word "penalty" to describe the process of normalizing songs to have the same loudness.

I have an album from a few years ago on streaming services that was mastered to about -9 on the LUFS scale. It sounds nice and loud on SoundCloud, which doesn’t do any normalization, but on Spotify, the normalization algorithm turns it down enough that it sounds noticeably softer than music by other electronic artists (although some of that probably comes down to my mixing skills versus those of experienced recording…

Considering the original EBU R 128 standard recommendation is -23 LUFS, these still seem to be crazy numbers to me. :)

Re: Loudness Penalty: Find out if audio will be turned down by streaming services

#40

Post by scopecreep »

cup-of-tea wrote: post #25
rcthompson wrote: post #2

I'm confused about why this website is using the word "penalty" to describe the process of normalizing songs to have the same loudness.

The idea is that clueless execs force mastering engineers to heavily compress the recordings to make them "loud". This shows the execs that if they do that, the streaming services will undo any extra "loudness" leaving them with just a compressed record.

A great example of this is the album Death Magnetic by Metallica.

The album version is compressed to hell but the version that shipped with Guitar Hero has none of that extra compression, presumably because someone who wasn't deaf mixed it.

The difference is night and day.

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