The Vocoder: From Speech-Scrambling To Robot Rock

Photo Gallery: The History of the Vocoder

[Interactive:Photo Gallery: The History of the Vocoder]

This graphic requires version 9 or higher of the Adobe Flash Player.Get the latest Flash Player.

This interactive content is not supported by this device.

The History Of The Vocoder

If you've listened to pop music in the past 40 years, you've probably heard more than a few songs with a robotic sound. That's thanks to the vocoder, a device invented by Bell Labs, the research division of AT&T. Though the vocoder has found its way into music, the machine was never intended for that function. Rather, it was developed to decrease the cost of long-distance calls and has taken on numerous other uses since.

Music journalist Dave Tompkins has written a book about the vocoder and its unlikely history. It's called How to Wreck a Nice Beach: The Vocoder From World War II to Hip-Hop.

Tompkins says the machine played a significant role in World War II. After the U.S. government discovered that Winston Churchill's conversations with Franklin D. Roosevelt were being intercepted and deciphered by the Germans, it decided to invest in speech-encoding technology. So the National Defense Research Committee commissioned Bell Labs in 1942 to develop a machine — and Bell Labs delivered.

The vocoder wasn't without its flaws. Intelligibility of speech sometimes proved a problem, but Tompkins says pitch control was a bigger concern.

"They didn't mind world leaders sounding like robots, just as long as they didn't sound like chipmunks," he says. "Eisenhower did not want to sound like a chipmunk."

From Military Base To Music Studio

The vocoder experienced a major transition from military device to musical effect when Wendy Carlos used it on the soundtrack for 1971's A Clockwork Orange. Carlos did a vocoder interpretation of the fourth movement of Beethoven's Ninth Symphony, which Tompkins says exposed the vocoder in unprecedented ways.

"Essentially, that introduced the vocoder to its first major audience," he says. "A lot people had no idea what it was. As the vocoder evolved, they knew the voice but had no idea where it came from."

After A Clockwork Orange, though it was still an expensive technology, the vocoder saw wider use in music studios. The German band Kraftwerk was one of the first musicians to employ it in its work. It fit perfectly, Tompkins says, because the band's work was primarily electronic.

Later, in the 1980s, the vocoder became the voice of electro-funk hip-hop. Michael Jonzun recorded what is believed to be the first hip-hop vocoder album, Lost in Space, in 1983. The futuristic sounds complemented the synthesizer, which became widely heard in music from that decade.

The vocoder is less prevalent in today's popular music, but its legacy lives on. Its successor is Auto-Tune, the pitch-correcting software prominent in popular music today.

Excerpt: 'How to Wreck a Nice Beach: The Vocoder from World War II to Hip-Hop'

How To Wreck A Nice Beach cover
How To Wreck A Nice Beach: The Vocoder from World War II to Hip-Hop
By Dave Tompkins
Hardcover, 336 pages
Melville House/Stop Smiling
List price: $35

In one word, militarism was funk.

—H.G. Wells

Axis of Eavesdroppers

I have been bugged all my life.

—Vyacheslav “Iron Arse” Molotov, Soviet Minister of Foreign Affairs, 1955

Theoretical security was not absolute like the records.

— Ralph Miller, Bell Labs

We are clear.

It’s quiet inside the Black National Theater, just above 125th Street in Harlem. Afrika Bambaataa sits on a defeated couch, flipping through a brochure published by the National Security Agency. He wears black sweats and fluorescent green running shoes, and there’s a trainer’s towel around his neck. The Thunderdome spikes, leather cape, and Martian sun dimmers have been left at home. He seems to be giving his myth the day off, looking more like a gym coach with a head cold than the retired gang warlord who once borrowed his mom’s records, stuck a speaker in the window and blew out the neighborhood.

Our conversation arrived at the NSA through the normal discursive channels: an old record Bam made that doesn’t exist, an admiration for a British vampire soap opera, a childhood memory of sneaking to the front row to watch Sly Stone “make his instruments talk.” Yet when discussing the NSA, Bam drops into a cautious strep basso. If anything can modulate our voices, it’s the notion of some federal protuberance listening in.

The brochure in his hands is pink and its title is not for the sore of throat. The Start of the Digital Revolution: SIGSALY Secure Digital Voice Communications in World War II. Bambaataa grunts and jots this down on a borrowed scrap of paper. On the cover is a dual turntable console photographed behind a nameless door in the basement of the Pentagon. Surrounding the turntables are banks of winking electronics, as if the walls are putting us on, spoofing a future that’s one set of pointy ears from campy. Taken in 1944, the photo, along with the future, would not be declassified until 1976. Bambaataa is curious, having spent 1976 DJing some of the better parties in New York. By 1981, he was making people dance to German records that spoke Japanese in voices programmed by Texas Instruments.

The Pentagon turntables are now sitting at the bottom of the Chesapeake Bay. These machines were designed by Bell Labs but created by funk, back when funk meant fear, German transmitters and codebreakers under headphones. The turntables played 16-inch records of thermal noise in reverse, a randomized shush, backwards masked inside out. Produced by the Muzak Corporation, the vinyl was deployed for the army’s “Secret Telephony” voice security system, a technology that was treated with the same crypto fuss as the Manhattan Project. Installed across the globe from 1943 to 1946, these fifty-five ton phone scramblers would be used for D-Day, the Allied invasion of Germany, the bombing of Hiroshima, and the “dismemberment of the surrender instrument”—allowing Roosevelt, Truman, Churchill and Eisenhower to discuss the world’s fate with voices they barely recognized, voices not human but polite artificial replicas of speech rendered from digital pulses 20 milliseconds in length.

The wall of knobs assigned this task was the vocoder, a massive walk-in closet of cryptology invented by Bell Labs in 1928. The vocoder divided the voice into its constituent frequencies, spread across ten channels, and transmitted them through band pass filters. At the receiving end, this information—stripped of intelligence and color—would be synthesized into an electronic impression of human speech: a machine’s idea of the voice as imagined by phonetic engineers. Not speech, they qualified, but a “spectral description of it.”

The vocoder was sensitive, high maintenance and seven feet tall, an overheated room full of capacitors, vacuum tubes and transformers. Some engineers dubbed this system “The Green Hornet.” Others called it “Special Customer.” Bell Labs referred to it as Project X-61753, or “X-Ray,” as if it was ordered from the back of a comic book with a pair of rubber Mad Doctor Hands. The U.S. Signal Corps called it SIGSALY, taken from children’s “nonsense syllables” and used for strategizing Allied bombing campaigns—the shelling. The New York Times, not knowing what to call it, went with “Machine that Tears Speech to Pieces,” and then later, like most everybody else, decided on “the robot.”

To a DJ like Bambaataa, the vocoder is “deep crazy supernatural bugged out funk stuff,” perhaps the only crypto-technology to serve both the Pentagon and the roller rink. What guarded Winston Churchill’s phone against Teutonic math nerds would one day become the perky teabot that chimed in on Michael Jackson’s “P.Y.T.” During World War II, the vocoder reduced the voice to something cold and tactical, tinny and dry like soup cans in a sandbox, dehumanizing the larynx, so to speak, for some of mankind’s more dehumanizing events: Hiroshima, Cuban Missile Crisis, Soviet gulags, Vietnam. Churchill had it, FDR refused it, Hitler needed it. Kennedy was frustrated by the vocoder. Mamie Eisenhower used it to tell her husband to come home. Nixon channeled one into his limo. Reagan had on his plane. Stalin, on his disintegrating mind.

The Seventies would finally catch the vocoder in its double life: secret masking agent for the army and studio tool for the musician. The machine that subtracted the character from the voices of Army echelons would ultimately generate characters in itself—the one-man chorus of be all you can be. Never mind the robots: what’s more human than wanting to be something else, altogether? Ever since the first bored kid threw his voice into an electric fan, toked on a birthday balloon or thanked his mother in a pronounced burp, voice mutation has provided an infinite source of kicks. In 1971, that first kick was delivered to the ribs of anyone who saw Stanley Kubrick’s A Clockwork Orange. In its big-screen debut, the vocoder sang Beethoven’s Ninth to Dresden firebombings while rehabilitating a murderer who wore eyeballs for cufflinks. It was quite an association.

Soon the vocoder began showing up on records, reciting Edgar Allan Poe and making sheep bleats. If a string section could be replaced by the synthesizer, then why not the voice? The vocoder thanked you very much in Japanese. It allowed Bee Gees to be Beatles. It just called to say it loved you. It allowed people to give themselves names like Zeus B. Held, Gay Cat Park, and Ramsey 2C-3D. It could sound like an articulate bag of dead leaves. A croak, a last willed gasp. A sink clog trying to find the words. Or the InSinkErator itself, with its wiggly, butterknife smile. In Neil Young’s case, it was a father trying to empathize with his son who suffered from cerebral palsy. Or it could’ve been just a bad idea—as I’ve been told, something that punished the atmosphere.

Shadowing the World War II model, the vocoder would have its own Axis powers: Kraftwerk (Germany), Giorgio Moroder and Italo-Disco (Italy), and Bambaataa’s Roland SVC-350 Vocoder (Made in Japan, where the Yellow Magic Orchestra did a vocoder version of “Tighten Up”). In 1976, when SIGSALY was sufficiently dated to be declassified and allowed in public, the vocoder was already well out in the open, nodding along in Kraftwerk’s daydream stretch of imagination called “Autobahn.” Before the Age of Scratching Records with Basketballs, Bambaataa and his Zulu Nation DJs would use more gathered German intelligence (Kraftwerk’s “Trans-Europe Express”) for their own version of travel, making people dance, forget, buy synthesizers, steal ideas, make more records, and dress like the Count of Monte Cristo. Countless electro and disco 12-inch singles owe their dance floors to the Thing That Tore Speech to Pieces. In the early Eighties, a romance better remembered than relived, the vocoder was the main machine of electro hip-hop, the black voice removed from itself, displaced by Reaganomics, recession, and urban renewal and escaping to outer space where there was more room to do The Webbo, where the weight was taken but the odds of being heard were no less favorable.

As the vocoder disbanded and digitized conversations in Washington, commercially available models were all over the radio, rapping ills and blight while generating the cosmically Keytarded fantasies needed to cope with it all. The vocoder would be used in songs about safety, Raisin Bran, taxes and black holes. Pods and poverty. A dance called “the Toilet Bowl.” Christmas in Miami and deep throats in Dallas. Nuclear war, biters in the city, and the Muslim soul. Saving the children and freaking the Freaks. The ups and downs of being a machine with feelings.

Though the military had originally wanted the vocoder to sound human, the Germans didn’t (calling it a “retro-transformer” as early as 1951) and somehow Afrika Bambaataa ended up with the keys to the robot. He calls the vocoder “that Joker.” “I couldn’t wait to get on that Joker,” he says. “We used to bring it to parties and funk ‘em up with it. Stop the turntables and I talk on that Joker. People were hearing the robot voice from the records but the records weren’t playing. They didn’t know what was going on.”

A man who wanted to use the vocoder to destroy all Pac Man machines once said to me: “People gotta like what’s going on even if they don’t know what’s going on.” And they did and they didn’t.

Of the World War II cryptology experts I interviewed, none were aware of the vocoder’s activities in the clubs, rinks and parks of New York City. (“It was just analyzing breakdowns of speech energy,” said the Pentagon.) Of the hip-hop civilians I interviewed, none were aware of the vocoder’s service in any war, nor were they surprised.

And none were aware that vocoder technology now inhabits our cell phones as a microscopic speck of silicone, allowing our laryngeal clones to sound more human, condensing the signal for more bandwidth at the expense of intelligibility in a shrinking world. The vocoder was originally invented for speech compression, to reduce bandwidth costs on undersea phone cables—the ultimate long-distance package. Now compression is back. The voices from the tower are not our own, but digital simulacra, imperfect to be real. Conversations are minutes gobbled and songs are ringtones chirping a T-Pain hook. Auto-Tune, the pitch-correcting software popularized by the robotox of Cher and inflicted on the twenty-first century, is often misheard as a vocoder, giving the latter currency through a revival of misunderstanding. Not as a technology, but a meme. In other words, it was what it isn’t.

When I mentioned this to Bambaataa, he nodded and said, “Yeahhh.” If conspiracy is your baggage, this is not unlike the way he says “Yeahhh” at the beginning of “Planet Rock,” a song he recorded with the Soulsonic Force in 1982, the same year Time magazine replaced its Man of the Year with a computer. Stocking dance floors for the past twenty-eight years, “Planet Rock” is the first hip-hop song to say shucks, vacuuming the sibilance, universally recognized as the white noise of secrecy. Over at Bell Labs, “shh” is called unvoiced fricatives, or “unvoiced hiss energy,” pulmonary turbulence modulated by tongue, teeth and lips.

“That’s bugged,” says Bam, who often speaks in terms of sound effects, as if waiting for the right word to show up. It may be a while, so bugged will do. Though much of Bam’s memory belongs to a record collection that defies mini-storage, you can always count on bugged, a hip-hop jargonaut that has survived for over two decades, its etymology based on the act of going out of one’s head through one’s eyes while attended by invisible (and apparently very busy) insects under one’s skin. When eyes “bug out” from their sockets, doctors call it globe luxation. Despite its provenance in pre-Industrial sanitariums, bugging out was the scourge of military argot during the Korean War, referring to US soldiers in a state of bullet-hastened egress. (Retreat was less a matter of going crazy than coming to one’s senses.) Yet losing one’s mind never goes out of style, and hip-hop, ever reinventing the tongue, would replace mad with bugged, converting the former into a quantitative adverb, as if rightfully assuming everyone is insane.

So crazy became bugged, the bugged picked up the vocoder, rappers went under surveillance, and we listened very carefully, under headphones.

+ + +

Bam continues chuckling through the NSA brochure, the towel, now over his head. He hits a circuit diagram and doubles back to the Pentagon, the glowing basement and the turntables. The room looks busy yet unoccupied. He wonders where they stuck that joker. Perhaps somewhere near the world’s most accurate clock. Or next to the Sumo air conditioner that kept the entire system from melting down. Or maybe behind the oven that stabilized the crystals that kept the turntables in synch 10,000 miles apart.

Those capacitors have some explaining to do.

By 1943, there were two turntables and a vocoder in the Pentagon and a duplicate system in the basement of a department store in London. As the war machine kept turning, vocoders and turntables would be installed in Paris, Brisbane, Manila, Frankfurt, Berlin, Guam, Tokyo, Oakland.

Oakland?

Another one, on a barge that tailed General Douglas McArthur around the Philippines. And another, under a mountain in Hawaii. If a satellite zoomed in on the northern bump of the African Zulu medallion hanging from Bambaataa’s neck, one could see General Eisenhower checking out two turntables and a vocoder in a wine cellar in Algiers.

Fall of 1983, the Zulu Nation funk sign began appearing on my spiral notebooks, its index and pinkie horns shooting lasers at whatever subject crossed its path. “Shazulu” became the code for “Latin Vocabulary Homework” which I did for a seventh-grade classmate in exchange for vocoder record money. (He would whisper over his shoulder from the desk in front of me: “You got that shazulu?”) I would launder the cash through Shazada Music, four walls of 12-inch singles in downtown Charlotte, North Carolina.

The Pentagon vinyl was far more rare, guarded with life but destroyed by protocol once the needle lifted. Bambaataa wonders if any of it survived. This was a world where records were controlled by clocks, not people. Where privacy was distinct from secrecy and a digit was referred to as a “higit.” Where torpedoes were equipped with 500-watt speakers and records played thermal noise backwards behind nameless doors. Where speech must be “indestructible” and the voice wouldn’t recognize itself from hello. So it’s not unreasonable to think that turntables and vocoders once kept the snoops out of Churchill’s whiskey diction.

Bam, often just headphones away from some version of deep space, is not surprised. (He once named an album Warlocks and Witches, Computer Chips and Microchips and You.) His old playlists could be a conspiracy theory themselves. To Bam, it’s William Burroughs, Gary Numan and Vincent Price who are the real vocoders. In a sense, everything is bugged.

He mutters something about “Leviathan” and scans through the NSA appendix. There’s a transcript of Bell Labs President O.E. Buckley speaking through a vocoder in Pentagon Room 3D-923, July 1943, when Special Customer was first activated. There is a promise of “far-reaching effects.”

We are assembled here today to open a new service—Secret Telephony. … Speech has been converted into low-frequency signals that are not speech but contain a description of it…Signals have been decoded and restored and then used to regenerate speech nearly enough like that which gave them birth… Speech transmitted in this matter sounds somewhat unnatural.

Bambaataa descrambles a frog in his throat, a matter of clearance in itself. Somewhat.

“We hope that it will be a help in the prosecution of the war,” said O.E., signing off.

And so we bug.

Excerpted from How To Wreck A Nice Beach: The Vocoder From World War II to Hip-Hop by Dave Tompkins. Copyright 2010 by Dave Tompkins. Excerpted by permission of Melville House/Stop Smiling. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.

Comments

 

Please keep your community civil. All comments must follow the NPR.org Community rules and Terms of Use. NPR reserves the right to use the comments we receive, in whole or in part, and to use the commenter's name and location, in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.