Hot Tubes and Static

There must be a million or more articles about which sounds better, AM or FM. I know that is an exaggeration but it seems that way to me.

The term “sounds better” is about as subjective a concept as there ever was. What sounds good or bad is truly in the ears of the beholder. For example Lawrence Welk sounds pretty bad to a Heavy Metal listener and hip hop and rap can’t be tolerated by most lovers of Doo Wop.

Here is my own personal take on it. There is no doubt that FM Stereo has a better clarity, lower noise floor and a crispiness that is not there in AM radio. But there is a soul to an old analog AM signal that just can’t be replicated by FM especially digital FM.

As for that soul, it comes from the fire of the sound being baptized in the glow of a hot final tube or two. The modern solid state AM transmitters don’t quite get it. Alas, there are not too many tube type AM transmitters around these days. They are just too expensive to operate. Those tubes are expensive to purchase, especially the higher powered transmitters. And much more electrical power is required to generate those signals.

The sweet spot of those AM signals was hit when those tubes kicked off just a bit of extra electrons in a blue flicker across the face of the tubes. That is when the sound coming out of those old blowtorches was perfect, perfect for AM that is. Those bass notes had an extra fire, the midrange was solid and the treble was… not there. Well, relatively speaking there was a “treble” of sorts, 6 to 8 kilohertz. In today’s FM world with treble ranging from 10 – 15 kilohertz. What was treble in the old AM days is midrange today. I must admit, that as I get older, I can’t hear those higher frequencies as well any more.

But those old AM car radios had big speakers in them. Those speakers could rock and roll with the double bass line of the Funk Brothers recorded in Studio A at Hitsville, USA on a Motown song, the rich instrumental mix of The Wrecking Crew in the California Music Scene or the hot buttered soul coming out of the Muscle Shoals Sound Studio at 3614 Jackson Highway in Sheffield, Alabama. Remember cruizin’ between hamburger joints with the radio turned up loud enough for everyone in the car to get down to the tunes but not so loud that it set of seismic alarms in the neighborhood. That was real, hot and sweaty rock and roll.

I must digress to one of my favorite peeves; boom cars. You hear them everywhere blasting out all kinds of music from rock, to country to hip hop and rap. To me that music experience is similar to taking a sip of water from a fire hose turned fully on. There is no subtlety, no finesse or artistry in that. Do you hear that when you go to a concert where the artists control the balance? No! Most artists prefer a more balanced approach to their music. You really can have power and balance.

End of rant!

Back to that warm AM sound. One of the other things that made me love AM was the fact that there was a little static in the sound. FCC regulations required that the DJ, if he or she was the transmitter operator, to listen to what the transmitter was putting out. What made that possible was the fact that there was no delay in the audio chain from the microphone to the AM receiver. Our headphones were essentially plugged into a radio tuned to the station. We had a much better perception of what was going out on the air through all the compression and processing required to keep the station both loud and legal. There was something magical about hearing the slight hiss of static behind the music and my voice. It almost made me feel like I was one with the station.

These days, the DJ on an FM station normally can’t listen to the transmitter because there is a 5 -8 second delay in the transmitter itself while it converts and processes the digital signal it receives from the audio board and broadcasts it. Most stations also provide a 10 second delay/dump system that allows the operator time to dump offensive material that may have initially gotten past them. We didn’t have that back in the day, and didn’t really need it because even the audience members calling in a live “Instant 60 Request” understood that if they abused their 15 seconds of fame, it would all go away.

I have a friend who retired from radio a couple of years ago that loved to hear the sound of the processing so much that he had the engineer build a duplicate audio chain that fed his headsets the same sound that the main one fed the transmitter. The engineer was fine with that since it provided a hot backup to the components that fed the transmitter and could be instantly patched over to the transmitter in case of a failure. Alas, that studio was torn down when that station moved to a location downtown and new studios without the duplicate audio chain were built.

These days, when I playback a show that I’ve done on WUSC-FM or one of my online shows, I am surprised that I made an error in mixing and that what I heard in my headphones was not what went out on the air. The processor handled the mix differently from what I expected. But that is the world we live in today. I’m just grateful that I have a chance to make those mixing errors. Oh MY!