The Hissing of Vintage Tapes

Today in Tedium: Audiophiles—especially those that just sued a label for using digital masters instead of the promised analog—may hate to hear this, but I love noisy recordings, particularly those with background noise and tape hiss. It’s such a perfect way to accentuate a rawness in the way something is recorded and performed, that adds an extra layer of static to the musical output. Some of my favorite music is loaded with noise and hiss—and I wouldn’t want it any other way. But I must admit that the battle against tape hiss was a necessary creative tension for the recording industry, one that helped to force innovations big and small in recording processes for nearly 50 years. Today’s Tedium leans into the noise. Sometimes it fades in, sometimes it fades out. — Ernie @ Tedium

So, what causes background noise like tape hiss, anyway?

When you hear a recording with a lot of background noise, there are a lot of possible reasons for this. The room may have a lot of background noise, and you might be using a faulty wire, which can introduce an unwanted sound.

But tape hiss is a special kind of noise. It isn’t caused by what’s recorded on the tape, but by the magnetic particles on the tape itself. You’re literally hearing the imperfections on the tape. I looked around for a lot of descriptions of what tape hiss was, and the best one I could find came from a 1992 issue of Recording Musician, written by engineer Paul White:

When making a tape recording, there are two main enemies—noise and distortion. Neither can be eliminated completely, but correct use of the equipment can ensure that both are minimized.

When I talk about noise during recording, I don’t mean the musicians, (though they often qualify). I mean the background hiss due to the electronic circuitry and, more importantly, hiss due to the recording tape itself. Because the signal recorded onto tape is statistical in nature, there is always some random element, which manifests itself as a background hiss. Even blank, unrecorded tape creates a hiss if you play it, as all the randomly charged magnetic particles conspire to create a random electrical signal—hiss.

To put this another way, it was a fundamental failing of analog tape, and something recording engineers like White were always looking to minimize in recordings.

And, of course, there are other sources of degradation that tape deals with, including flutter and wow, two forms of distortion caused by speed variations in the tape, whether from the recording or playback.

For decades between the period that professional tape recording came to wide use in the late 1940s and digital recording found uptake in the 1980s and 1990s, inventors and tinkerers with a background in audio engineering would come up with a wide variety of techniques to minimize hiss as much as possible.

The “Dolby B” system greatly reduced hiss on consumer cassette tapes. (Dominik Schneider/Unsplash)

Some worked better than others, and probably the best known is the system created by inventor Ray Dolby, who, as a teenage engineer at Ampex, helped build the first video tape recorder—a personal request from Bing Crosby that ended up changing the world—and later came up with his own namesake noise-reduction system, which was first produced for professional studios to help solve the problem of added noise to master recordings. The technique effectively compressed the sound upon recording but expanded it on playback, a technique based on Dolby’s thesis work involving improving image quality on X-rays.

Eventually, as tape became a preferred medium for consumers, a variant of Dolby’s technique, called Dolby B, was made for consumers as well. As a 1973 New Scientist article notes, Dolby’s “active filter” system wasn’t the first to remove noise in this way, but earlier systems tended to harm quality significantly in their efforts to remove tape hiss, particularly during quiet passages where added noise might be more noticeable. But Dolby’s system innovated in that it came up with solutions to reduce noise both in the recording process (by increasing the volume of the recording around frequencies most susceptible to tape hiss) and during playback (by lowering the frequency of that sound to its natural level). The result is a tape that works just fine in a conventional tape recorder, but sounds significantly better in a Dolby-supporting machine.

“In practice the tape hiss can be reduced to as little as one tenth its usual level, which is usually good enough to make the hiss virtually inaudible,” freelance writer Adrian Hope explained.

(The secret to Dolby’s success on the consumer market? Rather than creating better tape recorders, Dolby Laboratories licensed the technology. Everywhere.)

Dolby’s work helped to raise the profile of the compact cassette, which became a viable alternative to vinyl thanks to efforts to minimize the noise, and set the stage for his company to further innovate in areas such as consumer audio and film.

Speaking of film, an earlier hiss-removal system literally used it to pretty solid effect.

A TASCAM Portastudio 244. (via Wikimedia Commons)

How TASCAM brought tape hiss back into style

By the time the TASCAM Portastudio, a four-track tape recorder by the Japanese electronic company TEAC that used standard compact cassette tapes, came about in 1979, the music industry had fully embraced a more polished approach.

But the Portastudio, intended as a machine for the home recording of demos, ultimately proved a comeback story for background noise in popular music. When it was sold to the recording industry, the device, which weighed less than 20 pounds at a time when your only real alternative was spending a lot of money on more traditional studio equipment, was sold as a way to mess around with ideas rather than as the full package.

“You can pack it under your arm, plug it in anywhere and record merely by plugging in a microphone and headphone,” noted TEAC sales manager Bill Mohrhoff in a 1979 Billboard article. “The Portastudio is not forcing the musician to pay for specifications and other features he doesn’t want to need. But it does fulfill the needs of the songwriter/composer. What the Portastudio is not, however, is an audio/high fidelity product.”

It only took a couple of years for the Portastudio to find itself in the bedrooms of some of the music industry’s biggest stars, who immediately figured out that the fact that it wasn’t a high fidelity product was actually an asset. A little more than three years after the Portastudio 144 was first released, Bruce Springsteen sat in his Colts Neck, New Jersey, home and recorded a bunch of songs on one, bought by his guitar tech, in an effort to reshape his songwriting process so it would be more efficient and manageable, so that he could take a bunch of tracks to The E Street Band, rather than trying to write in the studio.

Instead, he accidentally created a recording that was so effective on its own that the band didn’t even need to be involved. That album became Nebraska, and it was a mainstream coming-out party for the Portastudio, with artists big and small embracing the tool after that. The engineers were in shock that such a thing was even suggested, that this random tape that had been sitting in Springsteen’s pocket for months was being proposed as his next album.

“We were all trained to get the best sound possible on the best equipment, and here was our artist asking us to go against pretty much everything we knew,” recording engineer Toby Scott told TASCAM in 2007.

But eventually, they went for it. The tape hiss was really bad on it—notably, Portastudios don’t use Dolby noise reduction, but an alternative system called dbx, and even then, hiss was a constant problem—and required some engineering work to even get it to the point where it could be released in a vinyl format. But eventually, it was.

But the album’s famously low-stakes recording process serves up a reminder that even the lowest of the lo-fi can still use a lot more polish. Even though most of the songs Bruce recorded that day ended up being released in modestly polished demo form, the best known song actually survived the studio session in which it was realized that Nebraska was already basically perfect: The official recording of “Born in the U.S.A.,” one of Springsteen’s biggest hits, came out of the “Electric Nebraska” sessions.