Sneaking Past Heavy-Handed Audio Compression on YouTube

niceone writes "Recently YouTube seems to have started applying extreme compression to the audio of uploaded clips. This is the type of compressions used by radio stations to make everything louder, but in this case applied extremely badly. In quiet passages, breathing and shuffling become overpoweringly loud. A gently plucked guitar chord becomes a distorted thud. Listen to an example here. And here's what it could sound like — still not perfect, but a whole lot better. The fixed version is thanks to a workaround proposed by Sopranoguitar — the idea is to turn down the audio and mix in a high frequency sine wave (I used 19kHz). The sine wave fools YouTube's compressor into thinking that the file is at a uniform level (and does not need the volume changing at all) but is filtered out by the encoding process (so, no need to worry about deafening any dogs)."

Comments

Update

[niceone]

After some more testing it seems that there is a problem with high quality mode. With the tone and sample rate I used (19kHz and 44.1k) at least the high quality encoder whistles at, some other frequency. Sounds like somewhere less than 10kHz to me.

I hope YouTube fix this soon.

Re:This hurts

[drspliff]

The worst examples I've seen have been videos of a lecture/speech, and while the main speaker has a microphone it also picks up sound from around the auditorium or lecture hall.

Normally this is fine as we have all become accustomed to faint background noise, with this extreme compression the faintest cough or shuffling in the audience sounds is as loud as the person speaking and is thus very distracting.

Considering most of the lectures I view are 30+ minutes long this really pisses me off.

Re:and who came up with it?

[billcopc]

Louder is one thing, compression is another.

Compression can help bring out the faint natural harmonics in a sound, making it "warmer", not unlike an overdriven tube amp. These harmonics are like ear candy to most people, subliminally making the sound more enjoyable.

Radio stations do it for various reasons, one is it helps them sustain peak output power. Another is that the average radio is a cheap chinese gadget that sounds like liquid ass, so the compression actually helps with the sound quality on those devices. When you also consider where radio is often heard, e.g. malls, outdoor venues, cube offices, you realize these are all substandard listening environments where high dynamic range really means you lose half the sound, so the compression again helps with perceived quality by driving most of the content above the noise threshold.

There are plenty of good reasons for sound compression, but its use should be toggled by the user, and for the love of god, give it some sane thresholds! For most content, anything above 4x compression is overkill!