The Joys of FM

The Joys of FM

Written by Andy Schaub

Although it’s common for more than person to discover or invent something, these names come from my own history, so they hold special importance for me, and are as correct as I think these things get outside of a true history book. I do wish more women were credited for the contributions they have surely made.

I. Guglielmo Marconi

In December of 1894, Guglielmo Marconi sent the first known wireless signal no more than a few feet across a room by, basically, capturing – with what we now call an antenna – the power of a spark that emitted an electromagnetic signal, indirectly triggering a bell. He continued to conduct experiments and to develop the technology until 1909, when he shared the Nobel Prize in Physics for developing RADIO (Rural Area Delivery of Information and Organization). Although Marconi learned that more power and longer, higher antennae could send the signal farther, no technique to multiply or amplify the signal existed until 1906, when Lee de Forest invented the triode electron valve (vacuum tube), a precursor to audio tubes like 2A3s and 300Bs, and so on.

II. Lee de Forest

The genius of de Forest’s invention lay in its not actually amplifying the signal but in making a copy that was analogous (hence “analog”) to it with more force or power by having an emitter (cathode, a piece of wire in an airless globe) heat up to the point that electrons would fly off it in concert with the incoming signal, strike a heated wire mesh (or plate), and for every one electron to strike the plate, two or three would fly off and arrive at the collector, another piece of wire that now carried a signal that was an imperfect copy of, but analogous to, the input signal, with more force (watts as a combination of amps and volts) than at the input. (Everything distorts, analog or digital. It’s just a matter of how much it bothers one in practice.)

Lee de Forest, holding two early vacuum tubes. Boy, do we owe this guy a debt of gratitude

Lee de Forest, holding two early vacuum tubes. Boy, do we owe this guy a debt of gratitude!

 

III. Edwin H. Armstrong

This first type of wireless transmission was called AM (amplitude modulation), which worked by varying the amplitude of a carrier wave in correspondence with the audio signal. This implies that (without using an awfully lot of math), the more compressed the dynamic range of the original signal, the greater the overall fidelity of the transmission. Of course, uncompressing the signal was either problematic or just not done, so, on December 26, 1933, Edwin H. Armstrong received a patent for FM (frequency modulation), where the frequency of the carrier wave varies with the audio signal). No amplitude compression or expansion was required; so no dynamic range compression was necessary simply to send and receive the signal. This resulted in higher sound quality and less intermittent noise (or static). Remember, though, that this innovation was still mono, not multichannel (stereo, or multicasting).

IV. Alan Blumlein

FM stereo, or two-channel FM (and the whole idea of multichannel sound) was the brainchild of a British engineer. In 1931, Alan Blumlein and his wife were at a local theater. The sound systems of the “talkies” had a single set of speakers (mono), leading to a somewhat disconcerting effect of an actor being on, say, the left side of the screen with her voice coming from the right or center. Blumlein suggested that he had found a way to make the sound follow the actor across the screen by having several “channels” or sources of sound (originally three). Apart from its intrigue as a technical innovation, the introduction of multichannel sound in the 1930s helped to draw people back to cinema, as the advent of television in the mid-1920s and its growing popularity after World War II had taken attention away from movie theaters. The introduction of stereo (or two-channel) as opposed to multichannel sound had more to do with the limits of the predominant home media, vinyl LPs, than an aesthetic choice.

V. James T. Russell

While many sources suggest that Sony and Phillips invented the CD, James T. Russell (not Kirk) is the true father of the medium, having created the first functional prototype of the CD (converting analog to a digital medium and back again during playback) in 1973. While the early commercial success of the CD in the early 1980s had more to do with Tower Records than anyone else (thank you, Colin Hanks), it was a godsend for FM radio stations because of its characteristic lack of noise and overall good sound, and ease of cueing; plus, Studer made a commercial CD player for studios with wonderful sound quality and reliability. Despite the promise of “Perfect Sound Forever,” (as claimed by a 1982 Sony ad campaign), the advent of streaming decades later has slowed CD sales to such an extent that many companies have stopped making CD players and CD transports altogether (a premature move for sure, but such is the market from a short-term-only viewpoint).

VI. Rob Robinson et al.

Rob Robinson at audio software and hardware company Channel D did something brilliant a long time ago that perfectly illustrates the bridge between analog and digital and back again that necessarily occurs with almost all modern recordings. There really are no digital microphones or speakers, not in the literal sense, because sound is analog, pure and simple; but the conversion between analog and digital is, conceptually, much like the modulation/demodulation that occurs in AM and FM radio via tuned circuits.

Pure Vinyl software screen shot.

Pure Vinyl software screen shot.

 

Rob created an app called Pure Vinyl that makes it simple to rip vinyl manually (with easy step-by-step instructions. Pure Vinyl employs super-precise digital RIAA correction, and no noise correction; and it sounds stunning, in some ways more “vinyl”-like than vinyl, from what I’ve heard. It is also great fun. However, the ripping process does take a while. Channel D also manufactures high-quality phono stages.

VII. Steve Silberman and The Cybermen

By “The Cybermen,” I mean the clever team at Roon, the music software and music player company. They have been able to use existing shareware and their own engineering and intelligently bring it all together down to the kernel level, which is a big deal in Linux and other operating systems to do what Roon does so well in its music playback user interface. You get more control of the experience in every sense. In my opinion and many others, it is the first example of true software elegance in high-end audio circles. No need to deal with Windows CE, ever! Roon is the latest metaphor for a home jukebox, but with super-high-end sound that makes streaming so much fun. (But still, nothing really replaces vinyl.)

VIII. Jim Richards of Magnum Dynalab

Folding back to the joys of FM, Jim Richards and Magnum Dynalab have always made wonderful FM tuners, and now, SiriusXM and internet tuners, media servers and all sorts of other cool gear. However, I’ve always wanted to have what I think of as their “urban apartment configuration”: the Signal Sleuth FM signal amplifier, and their SR-100 indoor adjustable FM antenna. I would be able to tune in a lot of stuff with those, almost as clearly as with cable FM, (which really used to exist), in an apartment in San Francisco with lots of hills and the presence of great amounts of IM distortion.

IX. Norway

Sadly, FM as we know it seems to be going away in favor of digital audio, which does make more efficient use of the airwaves. Here’s what happened in Norway (from a report in TIME):

Starting on Wednesday – at precisely 11:11:11 a.m. on Jan. 11 [2017] – Norway began shutting down its FM radio network and replacing it with digital radio, a process that will be complete by the end of the year. Digital radio promises better sound quality, more radio channels and reduced costs. Still, many aren’tt psyched about the switch. They say two million cars in Norway dont have digital receivers, and converters aren’t cheap, reported Reuters.

Norway is a small test, and most people I know who still use broadcast television in the US (I know it’s not a precise analogy) are very happy with digital video. And, I just have to ask” is it now illegal to broadcast analog FM in Norway, or does no one even bother to listen to analog FM there now?

X. Andy Schaub

I’m not being narcissistic; but, when I was a kid, I would record fake radio shows on an old reel to reel deck, then play them through my speakers. My dad had this little FM transmitter that had a range of 300 feet, with RCA connectors that I plugged the tape recorder into. It took a while for me to dial in the transmitter’s very-low-amplitude signal at XX.00001 #Hz on my FM receiver, but I did, and it just stunned me how magical it was that I could hear my own voice from a recording playing on an FM radio, with no physical connection, just because of an almost literal resonance of the electromagnetic ribbons around me.

It’s a bit like standing in an arch where you can hear someone whisper from far away. If you leave the arch, the whisper is still there, just like the way the electromagnetic waves encoded with FM music still float in some electromagnetic river and wait to be heard before they all fade away.

Header image courtesy of Pexels.com/Ksenia Chernaya.

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