Wednesday, June 13, 2007

How Loud?

A friend of mine recently sent me a sound article by Adam Sherwin, media correspondent for the New York Times. I'm always glad to see sound addressed in the media but I also felt the need to respond - first, to a comment or two by my friend, then to points made in the article.

dB: The writer makes some good points about volume and lack of dynamics in today's recorded music. What he fails to mention is that moderate compression was used in the vinyl days precisely to keep the needle from jumping the groove; and that serious compresson started not with records but with AM and FM radio's processing of the signal. First, it was done to get the signal to travel as far as possible and stay within the FCC's power restriction for that frequency; but then came the competition among stations -- who had the "loudest" signal on the radio band? Research and common sense show that listeners tune in stations that are loud and clear and if you're compressed, you increase the odds of being clear further away.

My friend: "It started with Dolby..."

dB: Dolby was a method that dealt with noise compression. When used appropriately it seriously improved the quality of analog mulit-track recording; and for better or worse Dolby (along with CrO2 and Metal tape formulations) extended the life of cassettes as a commercial and personal format. This led to the "cassette revolution" that democratized the album release, putting it in the hands of every garage band. The internet, recording software, websites, and downloads have fueled this revolution and major labels are the loosers.

My friend: "I feel bad for headphone listeners today."

dB: Yes, me too; and to make matters worse: 1) advancements in headphone quality allow listeners to turn up the volume more before distortion occurs; 2) advancements in headphone comfort invite listeners to wear them for longer periods of time. Both contribute to severe hearing loss.

Sherwin: "Dad was right all along - rock music really is getting louder and now recording experts have warned that the sound of chart-topping albums is making listeners feel sick."

dB: I was working for the American Forces Radio Network in Belgium in the early 70s. That's when bars and nightclubs started installing dual turntables so a DJ could crossfade danceable music just like radio stations did; and big sound systems so the music could be as loud as a live band played. The result was a discoteque, and it wasn't long before record companies jumped on the band wagon with a formula and created the marketing term "disco." A health issue developed (at least in Belgium at the time) that was labeled "the disco dump." With long wavelength bass frequencies so loud, it put pressure on the internal organs; and some lost bowel control on the dance floor.

Sherwin: "Record companies are using digital technology to turn the volume on CDs up to '11'."

dB: A good trivia question: What movie produced the "turn it up to 11" phrase? [Spinal Tap] And what do Spinal Tap and The Simpsons have in common? [Harry Shearer acts in both. Check out www.harryshearer.com/ ]

Sherwin: "'Peak limiting' squeezes the sound range to one level, removing the peaks and troughs that would normally separate a quieter verse from a pumping chorus."

dB: No, peak limiting removes only the peaks but leaves the troughs. Hard compression removes both.

Sherwin: "The process takes place at mastering, the final stage before a track is prepared for release."

dB: Yes, but compression also takes place during mixdown as individual tracks can get compressed prior to the entire stereo mix getting compressed.

Sherwin: "The CDs induce a sense of fatigue in the listeners. It becomes psychologically tiring and almost impossible to listen to. This could be the reason why CD sales are in a slump."

dB: Yes, compressed music without dynamics is extremely fatiguing, but corporate CD sales are in a slump because of illegal downloads, and independent artists distributing their own music (CDs at concerts and downloads on websites). Much of this is not part of reported national CD sales.

Sherwin: "Downloading has exacerbated the effect. Songs are compressed once again into digital files before being sold on iTunes and similar sites. The reduction in quality is so marked that EMI has introduced higher-quality digital tracks, albeit at a premium price, in response to consumer demand."

dB: This is why I don't care for mp3s. Some people either don't hear the difference in quality, or don't care, or both. Free music (illegal downloads) and convenience (iPods and cellphones) are winning out over high fidelity.

Sherwin: "In an open letter to the music industry, he asked: 'Have you ever heard one of those test tones on TV when the station is off the air? Notice how it becomes painfully annoying in a very short time? That's essentially what you do to a song when you super-compress it. You eliminate all dynamics'."

dB: Questionable metaphor: 1) the test tone has no dynamics on purpose because it's supposed to provide a constant volume; 2) the test tone is in the mid-range (1kHz) where our ears are most sensitive.

You can read Sherwin's entire article "Why Music Really is Getting Louder" at: entertainment.timesonline.co.uk/tol/arts_and_entertainment/music/article1878724.ece

2 comments:

THE GREAT LAKES KNUCKLEBALLER said...

Great thoughts, Dan.
I'm also struck by how easily this writer (and many others) conflate level compression and data compression. The two couldn't be more different in terms of what they do to the music, though both can be used to detriment.

We are in listening in the era of "good enough," though, and what happens when ITunes can get the bandwidth up to the barely - if at-all - noticeable 320kbps? What about AACs vs MP3s? Will audiophiles shriek? Will anyone care since even the best home theatres are contending with the noise outside, the fridge, the heater?

I like the blog and expect to read it regularly - and I'll link to it! Wish I'd known about it from the get-go!
Jim

The Guy You Thought Was Rude said...

I was watching Mythbusters and they tried to prove the Disco Dump. The guy was put in a box and low frequency sounds, inaudible, were blasted all around him. He had headphones on and could feel the vibrations on his face and chest, but no reported loss of bowel control.

Ed P.