Audio gain in volume signals loss for listeners

Despite serious concerns about their artistic integrity, members of the Seldon Plan agreed to crank up the volume on their latest album.

The Baltimore-based band had a good reason: They want your attention. And so does everybody else.


That's because studio engineers are pushing the envelope on technology that makes recordings sound louder than ever before - ensnaring listeners in an audio arms race dubbed "The Loudness Wars."

"The level of compact discs went up about 20 decibels in 20 years," observed Bob Katz, chief mastering engineer of Digital Domain, a sound studio in Florida.


To make this happen, engineers filter out the normal peaks and valleys of musical performances - and boost the volume of everything between. The technique also shows up in TV commercials that are much noisier than the programs they sponsor.

In the music industry, it has produced a generation of recordings that lacks the subtlety of earlier releases. Some experts also fear that it contributes to long-term hearing loss.

"This is horrible for the recording industry," said the Seldon Plan's Mike Nestor, who plays guitar for the up-and-coming indie rock group. "But we had to compromise our principles to get noticed."

Across the industry, the escalation in loudness was so gradual that average listeners rarely noticed the assault on their ears.

"It was like a frog put in warm water and heated slowly to a boil. It doesn't realize what's happening to it," said Charles Dye, a veteran Florida sound engineer. ""

Hearing specialists worry that louder recordings, played through tens of millions of iPods and other digital players that blast music directly into the ear canal, could produce an epidemic of hearing loss.

"As a culture, we are becoming more used to loud noise," said Monita Chatterjee, a hearing specialist at the University of Maryland, College Park. "I really feel like we are pushing it."

Proponents of "dynamic range compression," as the technique is known, argue that it makes recordings easier to hear - at least when it's applied artfully.


Most listeners, they note, do not use high-end audio equipment, which can capture every nuance of a performance.

They're far more likely to listen in noisy cars, through iPods or other digital MP3 players, and on computers. "For people who can't afford an expensive system, it brings out the things that need to be brought out," said Peter Cho, a sound engineer who works with artists at Universal Music Group.

But others equate the loss of nuance to a chef who mask subtle flavors with too much salt.

Consider Pink Floyd's 1973 album The Dark Side of the Moon, widely regarded for its rich range of sound. "You get emotionally tied up with the songs," Nestor said. "You're listening really hard. And when it gets loud again, it's an emotional release."

New recordings often lack that emotional resonance, said the guitarist, who runs a small record label called Beachfields while working on a doctorate in neuroscience at University of Maryland School of Medicine. "You've basically gotten rid of the peaks and valleys."

Those peaks and valleys - the quietest and loudest sounds - define a song's dynamic range, which is measured in decibels (dB).


Suspecting that noisier albums would attract more listeners, producers began seeking ways to boost loudness during the vinyl record era.

But vinyl's physical properties limited the loudest sound a record could produce. So engineers applied sleight-of-hand: They amplified the quieter sounds, squeezing them closer to the recording's loudest sounds.

"It's an odd perceptual thing," said Nestor. "Compression makes everything seem louder."

Producers called it "hot" music, and soon bands, record labels and sound engineers were competing to make their recordings the hottest. Meanwhile, producers of TV commercials used the same technique to hook viewers - or send them scrambling for the volume control.

Eventually, vinyl record producers reached the limit of the medium - compressing the dynamic range further would make the needle jump out of the groves. But the advent of digital music on CDs 25 years ago erased those limits - and set off another battle for survival of the loudest.

Mike Vasilikos, program manager at WTMD, Towson University's eclectic radio station, said his disc jockeys often notice this musical generation gap.


"We don't just play music from one decade or genre," he said. "There is disparity between the levels - it's definitely noticeable."

Some notoriously loud records have emerged in recent years, including the Red Hot Chili Peppers' Californication, Ricky Martin's song "Livin' La Vida Loca," and a re-release of the Stooges' 1973 album Raw Power.

Iggy Pop, the Stooges' lead singer, believed that the original release of Raw Power never quite captured the band's punk intensity.

So he remixed the original recordings in 1997 and urged audio engineers to compress the sound to extreme levels.

"I loved it, but they had a panic attack," Iggy said in a CD jacket interview. "It sounded like the speakers were going to explode, bleeding and melting and distortion."

These grinding walls of sound make hearing specialists nervous. That's because hearing loss depends not just on the loudness of a sound but also on its duration. An adult, for example, can listen to 85 dB noise for eight hours before suffering hearing damage but can tolerate 88 dB for only four hours.


The quiet parts of original recordings allow the listeners' ears to rest between loud parts, but heavily compressed music lacks those breaks. "It's a lot easier for people to expose themselves to loud sound now," said Sig Soli, a hearing researcher at House Ear Institute in Los Angeles.

Soli said he worries about iPod kids in particular, because their ears are still developing. "We don't know what the safe exposure level is for children," he said. "It takes a number of years to produce hearing loss, and it will take years to see the direct effects of iPod technology."

On the other side, Peter Cho, who works closely with Vlado Meller, one of Universal's top engineers, defended tasteful compression. Meller has mastered CDs for a wide range of artists, such as singers Celine Dion and Julio Iglesias and metal bands Metallica and Slayer. Many request some compression, Cho said, because it enhances their recordings.

He also noted that not all music is intended to be subtle. "It's not always about dynamic range," he said. "There is also the hard rock effect and a pounding approach."

Still, he acknowledged, "People are pushing it beyond what might be tasteful at times."

Charles Dye, who has mixed records for Bon Jovi, Ricky Martin and Sammy Hagar, said many artists would rather have a full range of sound but worry that consumers will turn up their noses if the overall loudness seems too low.


"You wouldn't want fans who buy the record to think there was something wrong with the CD," he said, "when really all they need to do is grab the volume knob and turn it up."

With that in mind, Dye teamed up with other sound engineers to form Turn Me Up!

The nonprofit organization encourages full dynamic range on recordings. It hopes to certify music with stickers that read, "To preserve the excitement, emotion and dynamics of the original performances this record is intentionally quieter than some. For full enjoyment, simply Turn Me Up!"

"We're not criticizing people who use compression," he said. "We're simply trying to give artists back the choice to make more dynamic records."

Producers are most likely to use aggressive dynamic range compression on hard rock, hip-hop and dance music. The Seldon Plan's Nestor said it's becoming more common in independent rock, too, but "indie labels tend to be hush-hush about it."

"We walked into the mastering studio," Nestor added, "and the engineer said, 'Look - if you want your CD played on the radio and TV, it has to be at this certain level.'"


Nestor said the compression was moderate but still noticeable. "Whenever the snare drum is hit," he said, "I can hear how much louder it is than when we normally record it or when we play live."

The concession might have paid off. Nestor said MTV has expressed interest in making tracks from the new CD into background music for a show.