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Comment by mortenjorck | Hacker News Reader

For practical listening, I actually prefer modern brickwall mastering techniques to more traditional mastering with a high dynamic range, for one reason: what the author sees as "hijacking the volume control from the listener" I would consider the opposite.

With a high dynamic range, a headphones listener may feel the need to adjust the volume several times in a song to boost the clarity of softer sections or to make louder sections more comfortable to the ears, depending on the listening environment. With a "loud," low dynamic range, however, the listener need only adjust the volume once, as the whole track is roughly the same volume. In other words, the listener is in control of the volume, rather than the engineer.

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Just give me the option. When I'm in the car, I like the "wall of sound" since it's a noisy environment, so I have a head unit with a built-in compressor I can control. When I'm at home, I prefer the dynamic range. The problem comes when the engineer takes that option away from me (quite often) clipping and distorting everything to the nth degree. Like the article mentions, this creates ear fatigue and I end up, eventually, just not wanting to listen to the CD at all which colors my perception of the band. So I'm less likely to go to their concerts and give them money. That's just me though.

As an analogy, how about if all text was served to you as .png files where the person writing the text has guessed what size text you want?

This is vaguely equivalent - it is difficult to go from image->text, just as it is difficult (or impossible) to go from low dynamic range -> high dynamic range. The reverse direction is cheap (and possible).

In fact, some compression codecs even have well defined compression curves to use - so your codec isn't just "bitstream in, pcm out" it is "bitstream+listening environment in, pcm out".

Isn't it more like the artist wrote his text using all kinds of font sizes that require the user to zoom in and out all the time to read it comfortably? Compression would mean that the range of font sizes is compressed so that one zoom level works reasonably well for the whole text.

> boost the clarity of softer sections or to make louder sections more comfortable to the ears

You can create these effects during playback with a compressor, which are available in many players[1]. Knowledge about compressors isn't as widely known as it should be; it's an important feature that would help a lot of people, especially anyone dealing with hearing loss.

> headphones

Maybe try better headphones (or a different type, such as enclosed headphones with good room attenuation)? Many cheap[2] headphones have terrible response to different volumes; quieter parts may be overly attenuated, for example. Cheap/bad headphones also tend to have a highly variable frequency response, which can sometimes sound like volume problems. If this is the case, spending some time with a highly configurable EQ might help (possibly in addition to a compressor).

[1] also available in some audio systems (e.g. jack) and as a feature in some drivers/soundcards

[2] and some "name brand", such as older Bose, anything Beats or other brands sold as fashion statements.

edit: re-added sentence that died during a bad copy/paste

edit2: Appendix for anybody that isn't familiar with dynamic range compression.

> need to adjust the volume several times

This is literally what a basic compressor is automating[3] for you. It turns down the output volume when the input level is over a threshold. There are a lot of (often configurable) details like how much to reduce the volume as the input level increases past the threshold, how quickly[4] it responds to a loud transient, and how quickly it returns to normal when the input becomes quiet again. Really nice compressors even smooth[5] the changes near the threshold so the whole effect is less noticeable.

[3] https://en.wikipedia.org/wiki/Dynamic_range_compression#Desi...

[4] https://en.wikipedia.org/wiki/Dynamic_range_compression#Atta...

[5] https://en.wikipedia.org/wiki/Dynamic_range_compression#Soft...

I knew about them and the copy of Android I had installed on my phone included compression.

Like most things in that OS it's very buggy, one day it just dumped full volume noise into my headphones and that really hurt. After that I hardly trust anything in Android to handle audio and don't like plugging headphones into my phone.

Out of curiosity, when did that happen?

There is value to constant volume, but I think a lot of the loudness war came from a time when there implementing a compressor on the user's side was expensive. It's trivially cheap now, basically every device you own that can produce audio now is capable of implementing a decent digital compressor with no additional hardware costs and about 5 minutes of an software engineer's time. If this wasn't hard when the loudness war set in, we'd probably just have a checkbox that defaults to 'on' in all these devises instead of the master being messed up. In other words, the timing of cheap, low power audio DSPs missed the boat by a couple years.

That's like saying you want low dynamic range on all of your photographs so you can see every detail. Dynamic range is an integral part of music

> That's like saying you want low dynamic range on all of your photographs so you can see every detail.

Which is actually a super common problem in amateur and even some pro photography today. "High dynamic range" (HDR) lets you capture an image with a greater dynamic range than the sensor itself can detect, usually by stacking a few photos taken with different settings. It preserves details that would otherwise be lost in shadows and highlights.

In other words, it's compression for images. And it gets over-applied really often, leaving hideous painful to look at photos. They end up too flat and in your face.

> In other words, it's compression for images.

No, it’s not.

There are two parts to this. First is capturing a HDR image, either by stacking photos or using a sensor with a good dynamic range (and capturing in raw). This is a good thing as you are capturing more information.

The compression you talk about is called tone-mapping and is used to make it possible to view HDR images on a non-HDR display. It can either be (over) done intentionally or it can just be an unfortunate consequence of HDR displays not being mainstream yet. Fortunately HDR is becoming a thing now for TV’s so computers are sure to follow.

Now, viewing HDR material on an actual HDR display, that is something different and can look absolutely stunning.

> The compression you talk about is called tone-mapping and is used to make it possible to view HDR images on a non-HDR display.

Yes, and it's exactly how audio compression works. You have a fixed dynamic range and in input signal that doesn't fit in that range. So you attenuate the values near the endpoints (shadows and highlights in the case of imagery) to fit within the range while still leaving values in the midrange with their original spread.

> Now, viewing HDR material on an actual HDR display, that is something different and can look absolutely stunning.

Yes, but that's not what I'm talking about.

> Yes, and it's exactly how audio compression works. You have a fixed dynamic range and in input signal that doesn't fit in that range.

Not exactly. Audio compression is usually used to compress to a much smaller dynamic range than the output format or playback equipment can support. Some recordings compress to within just a few dB. With HDR pictures it's usually because the display is physically incapable of reproducing the image without compression.

>With a high dynamic range, a headphones listener may feel the need to adjust the volume several times in a song to boost the clarity of softer sections or to make louder sections more comfortable to the ears, depending on the listening environment.

Softer sections are created and meant to sound softer though. Boosting the volume only in certain sections is more like making your own mix...

Listening conditions make a big difference. I have a very dynamic version of Queen's Bohemian Rhapsody (source: MFSL CD) that sounds absolutely great at home but is unlistenable in the car. The average volume is just too far below the peaks, so you strain to hear most of the song with a noisy background.

It seems like car stereos should be where the compression takes place.

I have an even simpler wish. All I want is to comfortably listen to my audiobook when running without going deaf when Strava comes on to give me pacenotes. My kingdom for per-app volume control!

That's one benefit of podcasts. They often have lower quality but louder audio so I don't have to pump up the volume when I'm out and about.

It's easier to remove dynamic range on playback than to add it back in... don't many stereos have a "loudness" function which brickwalls the audio?

The "loudness" switch on stereo amplifiers is for loudness compensation [1], not compression.

[1] https://en.wikipedia.org/wiki/Loudness_compensation

Shouldn't it be called quietness compensation, then? :P

The effect you want - roughly the same volume through a whole track, can easily be achieved with tasteful use of compression. Some genres hardly need any to start with.

There are a number of albums that were mastered quite well that have a good dynamic range, yet still sound good in my car, on headphones, or at home on the big stereo.

The heavily compressed stuff just sounds bad all around.

Here's another good article that covers this: https://riprowan.com/over-the-limit/

softer sections are an integral part of the music. what you're asking is like forcing movies to have all scenes with a constant luminosity no matter if it's day or night.

softer sections are actually an excellent way to make other sections bang like crazy, just because of contrast. the brickwall mastering techniques are an invitation to neglect composition techniques and overall creativity. the drumcode label comes to mind…

In my opinion this is a software problem, you just need some automatic gain control (automatic volume adjust).

Do you also want explosions in movies to sound just as loud as whispers? Quiet parts of songs are meant to sound quieter, there's even special notation in sheet music for this.

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