Tag Archives: radio

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl

Cool history lesson from Paul.

Hertz

I can’t begin to count the number of times I’ve written the abbreviation, Hz—1 kHz, 1,000 kHz.

It is, of course, short for Hertz.

The car company?

Heinrich Rudolf Hertz was a German physicist who first proved the existence of electromagnetic waves. Invisible forces that had a specific periodicity (frequency) that later were named in his honor.

Invisible waves were first proposed by a Scottish fellow, James Clerk Maxwell (no, not the hammer murderer Maxwell Edison) who first connected the idea that three forms of energy—electrical, magnetic, and light—were all related to each other. To make it even more interesting, they all seemed to travel at the same speed (the speed of light) and they all acted in the same way (like waves). He summed these conclusions up mathematically in what later became known as Maxwell’s equations.

It was our friend Hertz (no, not the owner of Hertz Drive-Ur-Self System), who would not only prove that which no one had yet shown, that electricity and magnetism could travel through space as waves (like visible light). It was easy for people to wrap their heads around the idea of light traveling through space because we could see it. But invisible electricity or magnetism? These were spooky, invisible, phenomena.

Hertz not only proved Maxwell’s Equations were correct, but in so doing, he also invented the first radio transmitter.

“Hertz’s first radio transmitter: a capacitance loaded dipole resonator consisting of a pair of one-meter copper wires with a 7.5 mm spark gap between them, ending in 30 cm zinc spheres. When an induction coil applied a high voltage between the two sides, sparks across the spark gap created standing waves of radio frequency current in the wires, which radiated radio waves. The frequency of the waves was roughly 50 MHz, about that used in modern television transmitters.”

Unfortunately, Hertz suffered from massive migraines and in 1894 died at the young age of 36 after complications in surgery to fix his condition.

Seems medical science was considerably farther behind than physics.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Country music

There’s all kinds of country music. Most of what I hear on the radio isn’t worth listening to. But the real music, the weepy, heartfelt, jazzy riffs, the fiddles, pedal steel guitar, the talent—the music you hear so rarely—touches my soul like few other forms of music.

Especially if it’s live.

We decided to head to Nashville to see what its music scene is like. What an unexpected pleasure.

Instead of big and expensive venues, nasty bouncers, and restrictive prohibitions on behavior, folks down south like their music up front, accessible and friendly. We were fortunate to get tickets to a sold out show at a small bar and grille in downtown Nashville, called 3d and Lindley. $20 a ticket to see Vince Gill and the Time Jumpers, some of the best musicians I have had the pleasure of listening to, with a big plus added in. Good sound. Really good sound.

Wow.

I took a not very good video from our upper deck vantage point and offer it here. Enjoy.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Those darn rules

I wrote of my burning desire to claim fame and fortune as a rock and roll disc jockey, in yesterday’s post. The college I attended had a class in radio announcing run by a grumpy professor by the name of Thompson. The station he ran played only to a loudspeaker, a totally deflating proposition for me and a few of my aspiring friends. We wanted the real deal, to be live and on the air.

I spent the summer building a control board and my friend had built a 250 watt AM transmitter, based on a Fender guitar amplifier for the modulator. We even had call letters figured out; KFJC. K because all radio stations west of the Mississippi required the letter “K” (W on the other side) and FJC for the name of the college. All we needed was a place to set up the studio. And it just so happened that attached to the student center was a vacant corner room with windows facing the open quad.

The radio club, as it was now known, had grown to about 10 members all eager to be on the air. If we could make this fly, most of Mr. Thompson’s radio class would bail and work for KFJC. I was elected its head. With hat in hand I approached the school board with our proposal, and it was a simple one. We would supply all the equipment, all the labor, take all the responsibility, and give Fullerton Junior College something to be proud of, run entirely by students. They should have been thrilled. But then reality struck.

One of the deans asked a rather obnoxious question. “Don’t you need some sort of license for a radio station?” The other deans agreed and told me to come back with a license, signed and sealed by the Federal Communications Commission, more commonly known as the FCC. Being a good salesman, I asked the right question. “If I return with a license, can we build the station?” The five caucused and their answer was, “yes”. I had been given marching orders, and march I did, to Santa Ana California and the offices of the FCC.

Tomorrow we learn how to run circles around bureaucrats.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Radio firsts

I have written much of my colorful youth and there are many stories to share, but I don’t think I’ve yet told you about my earliest radio career.

The year was 1967 and I wanted more than anything to be a rock and roll disc jockey with all the supposed benefits: women, fame, and fortune (and in that order). But I was instead pursuing higher education, not because I wanted one, but because it was a better option than being drafted.

California’s Fullerton Junior College had a radio announcer’s course taught by a Mr. Thompson, who had himself never been on the radio. Though not ideal, this seemed a natural foot in the door towards my lifelong goals–commensurate with the honest desires of most 18 year old males.

So I sat at attention with thirty others taking notes on diction, history, technique and everything that mattered not when it came to being a DJ. Little did I care of Emile Berliner and his invention of the microphone, or Marconi’s, or Sarnoff’s and the others, long dead. But that was the first semester. Semester two was sitting at the control board playing records and being a DJ–not on the radio, but into a loudspeaker broadcasting to the rest of the class. Lame. It was real radio, girls, adulation and riches I was after, not playing music into a speaker for 29 other 18 year old males lusting after the same things.

Another inmate–and I wish I could remember his name, perhaps we’ll call him Lance–told me he had actually built an AM transmitter and all he lacked to go on the air was an audio control board. I knew enough electronics to build one and spent the summer conspiring with Lance on a real radio station, something Mr. Thompson and his loudspeaker could never compete against.

My second year at FJC found me petitioning the school board for an audience.

More tomorrow.

Asheville, North Carolina ‘s Home Theater and Audio specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Wanna be a disc jockey?

Good Monday morning to you! Not sure why I started with that, but hey, Monday’s can be tough.

I promised yesterday I’d write a little bit about why the design of switching power supplies is so tough. We’ll then cover why they are not used so much in high-end audio.

Ever wonder how a radio station works? Whether AM or FM, radio stations (or for that matter cell phones as well) use a very powerful amplifier at their heart. That amplifier’s output is connected to a piece of wire called an antenna. In the case of a commercial radio station, the antenna is mounted high atop a tall tower. Coming into this powerful amplifier, called a transmitter, is audio, no different than what comes out of your stereo system’s preamplifier. What is different is what then happens to that audio signal before it reaches the output stage of the amplifier. The audio is passed through a device called a modulator and, depending on whether it is AM or FM, converted to a new form in preparation for being transmitted. I won’t go into what that form is, although it’s an interesting subject if you’re ever interested. No, what’s important is what happens next.

When you tune your radio dial to a station, you’re actually matching a frequency; the frequency of the radio station. That frequency is generated with a chopper, just like the chopper on the input of our switching power supply. When you turn power on and off quickly, you create a type of radio station. Just like your local AM or FM radio station, the chopper circuit we discussed yesterday is turning power on and off. If it does it quickly enough, it will broadcast that power through the air. Give it enough power and an antenna and you can broadcast for many, many miles. Or, you can do the same inside the chassis of your stereo equipment; something I am guessing none of us wants to do.

Most modern switching power supplies run at reasonably high speeds: from 50kHz to 500kHz and make very good radio transmitters. Only, that’s the last thing we want near our pure hifi equipment. Talk about pollution!

Remember I said a good helping of skill and, what some consider black magic, is needed to quiet those transmitters and restrict their broadcast areas? Now you know why. And radiated emissions through the air are only half the problem. When you switch large amounts of power quickly, the energy of turning on and off has to come from and go to somewhere. That ‘somewhere’ is the ground of your power supply and that ground is connected directly to, you guessed it, your sensitive audio circuitry.

But all hope is not lost for switching power supplies. The good news is this: their performance is wonderful. They are efficient, small, powerful and provide regulated low impedance power to circuits. They are a magnitude better performance in nearly every respect to that of a conventional supply. They are just noisy and hard to design. But there are talented people out there and some of the finest and quietest power supplies in the world are switching supplies.

And yes, to answer the question lingering in your mind, they are better, far better than conventional supplies. Only…

Asheville, North Carolina ‘s Home Theater and Audio specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

What do we have in common?

Balanced audio cables were invented many years ago for professional applications such as radio, television, film and recording studios. No consumer products had them. They were for the pros.

And the pros had noisy environments of many cables, inputs, devices, transmitters, and so forth to deal with. Their inputs were almost always transformer coupled. Meaning, an audio transformer was at the input and, for the most part, the output of their devices.

Using transformers kept ground loops at a minimum. Transformers also reduced noises from all the interactions of the equipment leaking into the connecting cables. Imagine a long run of audio cable between a microphone and a control room console. It could easily be upwards of fifty feet and along its path run close to power transformers, electrical outlets, perhaps even a radio transmitter if at a radio station. Lots of noise, lots of cause for concern. But the transformers isolating the equipment reduced much of this noise.

How did these transformers help with noise? As they were full range audio transformers they didn’t act as filters, reducing certain frequencies. No, instead they used one of the features of all transformers to reduce the noise. In fact, they rejected noise and accepted only musical signals. How did they do that? How did they separate noise from signal? What form of wizardry could account for this? The very same technology we’ve been discussing as of late; balanced audio.

Tomorrow let’s start to learn about something called common mode rejection.

Asheville’s Home Theater and Audio specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Content and Craft

In yesterday’s post I spoke about radio stations and how most terrestrial based AM/FM stations have gone down the tubes in their listenability. They are not alone: even the very music these stations play are suspect as well. Yet, there ARE good stations, just like there IS good music. One must seek it out.

I was in radio for years, as both an on air talent and a program director, so I have some level of insight into the field. I was fortunate enough to be involved during the heyday of music based radio, both top 40 as well as what we used to call AOR (Album Oriented Rock). Top 40 radio was at its peak in the mid to late 1960′s thanks to a brilliant programmer named Bill Drake who syndicated his sound through the Drake Chenault outlets. In the 1970′s FM radio went from background music to a medium that crushed AM in a very short period of time; and for the same reasons.

Throughout all these cycles of wild success to crashing failures, their were two common threads: the first was content the second was craft.

Content. Top 40 radio was not invented by Bill Drake, but he revolutionized it none the less. He took control of content from the sales department and put it in the hands of programming, maintaining tight standards in every respect. Instead of pandering to the advertisers, he ignored them completely and played to the listeners. This strategy went through a classic cycle: first upsetting the advertisers who bailed on the station, then building an audience who loved the content. The advertisers returned, hat in hand.

Craft. The very best FM radio stations of the day gave the content decisions to the air talent, each crafting their own mix of music. If the audience didn’t respond well to the mix, the air talent was replaced with someone who could do a better job. This is the exact opposite of what Bill Drake did. Drake controlled content with brilliant (but controlled) programming aimed at building an audience. AOR depended on the skill and craft of the individual to build audience.

Today, most radio stations, music services and many musicians are back in the hands of the sales and numbers people. Content and Craft suffer.

When we do discover Content or Craft, let’s all make a point of sharing and supporting those that “get it”.

Asheville’s Home Theater and Audio specialist presents Cane Creek AV and Paul McGowan – PS Audio, Intl.

Is it possible?

Can we ever hope to achieve a two-channel experience with music so real as to fool ourselves into believing there is an actual musician playing in front of us?  I mean sure we can close our eyes and imagine a live event is happening, but in all the years I have never actually believed it was real.  Close, but no cigar.

Over on the comments section of the post But does it sound like music? commenter Accuvox believes he has designed a loudspeaker system that can do exactly that, citing multiple examples of experiments he has personally conducted that fooled even the best musicians and listeners.  What I find fascinating in his comment are his observations about microphones and assumptions we have been making:

“I maintain it is impossible. Part of the reason is we have been asking the wrong questions since 1932. That year there were two seminal experiments that shaped audio to this day: The Blumlein experiment and the Fletcher-Munson experiment.

Blumlein was a genius, but stereo as we know it was a preliminary experiment with two ribbon microphones at 90 degrees. Blumlein was drafted before he could complete his invention, developed radar and died in a plane crash while testing an airborne version. In fact, his first guess was subsequently devolved because velocity microphones express depth better than pressure and pressure gradient microphones, which are used universally for “audiophile” recordings.

Fletcher and Munson made five major experimental errors. Their data was not too badly distorted by the mistakes.  Mainly they were asking the wrong question, which was frequency response.

We hear space through time domain variables of transient response and phase. The vicious cycle is that Fletcher and Munson’s methods were used to determine that humans are phase deaf.  This is flat wrong.

Because loudspeakers and reproduction chains mangle phase and transients and the subjects of large scale audiological surveys have all been radio listeners since before 1932, the false conclusions that HUMANS are phase deaf was extrapolated from the measured reality that radio and phonograph listeners are phase deaf.”

I can attest to the fact that we humans are far more sensitive to phase and time domain issues than frequency and noise.  Far more.

Asking the wrong question is a classic mistake many designers and inventors suffer from.  Me included.  I truly appreciate this new thought process brought forward by one of our readers.

Thanks for the insights and thought provoking dialog.  It is why I keep writing these posts.

Asheville Home Theater and Audio presents Cane Creek AV and Paul McGowan – PS Audio, Intl.

A trip to the radio store

In yesterday’s post I relayed the story of being banned from playing the kind of music I liked on the family stereo.  Not to be deterred, I set out to build my own stereo system so I could close the door to my room and play whatever I wanted.  I figured all I would need was a turntable, radio and a speaker.  I would build these three elements into a cabinet and have myself an awesome music making machine.

In the early 1960′s we had radio stores.  They don’t really exist any longer, but these stores typically had a radio repairman in the back of the shop and out in front various makes and models of radios, turntables, amplifiers and loudspeakers were laying about.  The store I was familiar with had a crusty old guy named Al that never put prices on any of the equipment in the front.  Whenever I would come in to browse Al would lift one eyebrow and glare at me, making sure I didn’t steal anything.  I’d never purchased anything from this guy but I did hang out a lot.

I had a budget of about $50 to work with having earned money over the summer as a darkroom tech at the local newspaper, the Anaheim Bulletin.  I certainly didn’t want to tell this old guy my budget but rather wanted to try and impress upon him the seriousness of my buying power, hoping he’d actually want my business.  I found an old hulk of a record changer sitting in a corner of the shop and asked Al if it worked.  ”It spins, the record changer’s broken, but it works.”  Since I didn’t own more than one or two albums at the time it seemed to be ok that the auto changing part of this turntable didn’t work.

“How much?”  Al would always size up his customers to see how much he could charge.  He knew I didn’t have any money.

“$10 bucks as is.”  Sweet!  I now had a turntable.  Since this unit was pulled out of an old console stereo, it had a couple of screw terminals in the bottom for the AC power and a few signal wires from the cartridge just dangling there.  I was pretty sure I could make this work in my new dream system.  But I still needed an radio.  ”What’cha gonna hook it up to?”  Al had this way of asking piercing questions as he peered over his Ben Franklin glasses, taking a drag of his Camel cigarette.  He always made me feel stupid.  I’ll never forget the ugly brown stains on his smoking fingers.

“I don’t know.  I need a radio to hook it up to.”  I was trying to sound like I knew what I was talking about in the hopes of getting some credibility out of the old duffer.

“You don’t need no radio, you need an amp.  Like this one.”  Out from behind the counter Al pulled an old, dusty tube amp out.  It was ugly.  It had obviously been inside some piece of stereo equipment in its long past and now it stared back at me looking for a home.  ”You put your turntable wires in here, connect your speaker up here and add a plug here.  It works.”  He lit a fresh Camel.

“How much?”  That took a while as Al sized me up.  He already had me for $10.  He took a long drag on the smoke, blew it up in the air in a thoughtful gesture.

“$50 and I’ll test the tubes for you.”

“I only have $50 total and I need a speaker too.”  I pulled the coveted wad of two $20s and a $10 from my front pocket and laid it on the table.  He just stared at the money, then looked at me in disgust.  He crushed the stub of his camel in an overflowing ashtray.  It felt like that’s what he wanted to do to me.

“Ok kid.  I’ll give you the amp, changer and a woofer for $70.  You can pay me later.”  Wow, I walked out of the store with a cardboard box filled with my new found treasures.  I was in.

Over the weekend I put together a tall cabinet the width of the turntable changer.  I had that mounted on the top of the cabinet.  Right below it was the amplifier with it’s power switch, volume and tone control knobs sticking out the front.  Below that was another box housing the single 8″ woofer.  That woofer had what is known as a whizzer cone that was supposedly a tweeter.  It was all magic and wonderfulness to me.

I wired everything together, got my good friend David Wiley to help me haul it down to the basement and there it was.  The most beautiful piece of audio equipment in the whole world.  David and I just stared at it.  He wanted it for himself.

Much to our surprise, it worked.  Tomorrow, the trouble begins.

 

Asheville Home Theater and Audio presents Cane Creek AV and Paul McGowan – PS Audio, Intl.

Happy new years to you and yours and may 2014 be a great year for us all.  PS Audio has a number of new products we’re excited about launching this year and I’ve been sitting on pins and needles waiting to tell you.  But that isn’t happening today.  Today we continue with our story from yesterday about first times.

Radio station engineer Jim Mussel invited me to his home to hear what I couldn’t at the station, so poor the Quadraflex monitors were.  Jim assured me that there were better speakers, better electronics and “something I’ve never heard before” awaited my arrival at his home.

We both lived in Santa Maria California, a sleepy little town along the Central California coast, inland from the water by about 30 miles.  It was a farming town, mostly sugar beets and strawberries.  Jim’s home was a modest 3-bedroom track house, the kind you see all over California.  They seem to spring up like mushrooms in a blink of an eye.  His stereo system was in the living room and occupied most of it.  In each corner was a JBL horn loudspeaker and on the table between the speakers, some ancient looking tube equipment.  Tubes!

“Jim, you have tubes?”  This was during the days when transistor based electronics was sweeping the country in the form of the Japanese receiver invasion.  Within what seemed a blink of an eye, not one stereo store I knew of carried tubes anymore, it was all solid state Japanese and American brands of receivers and integrateds.  I remember thinking how far technology had advanced us to be rid of these ancient fire bottles.

“Sure.  No one that really likes music listens to a receiver.  They sound awful.”  I learned that Jim’s “ancient” tube equipment was actually brand new and made by a company out of Minneapolis called Audio Research.  Both his preamp and power amp were from AR and they were pure tubes, fed from a Thorens turntable.

Jim turned to me and asked “what would you like to hear?”  At the time, one of my favorite tracks was Edgar Winter’s Frankenstein from the album They Only Come Out At Night.  The album featured an instrument I was very excited about, an ARP 2600 synthesizer.  At the time I was heavily involved in designing my own synthesizer and loved every aspect of these amazing instruments.  I played that track on the air quite a bit just because I loved the synthesizer solo in the middle.  So he cues up Frankenstein and lets it rip.

I was used to listening to this track on the radio station monitors and my headphones at the station.  I listened loudly.  The sound from the monitors was loud, but two dimensional and flat, as was the norm for the lackluster system at the station.  Only I didn’t know that.  I didn’t know that until I heard the same track on his system through the JBL corner horns.  That was a moment I will never forget and it changed my life and its course forever.  It sounded unlike the record I was used to from the very first note.  Then there was the dual drum solo and the synthesizer solo.  OMG.  The drums were pounding as if they were in the room.  Attacks of the snare and tom toms were so realistic it really did sound like the Edgar Winter group was right in the room.  I was stunned.  I had no idea.  How was this possible?

I think we must have listened to that track two or three times until he refused to play it again and wanted to put something else on.  I kept grilling him trying to find out why it sounded so different.  How could this make such a difference from what, I assumed, was a great system installed in the radio station already?

Jim patiently did his best to explain the world of high end audio to me but I didn’t get it.  What I did get was how much better it sounded than anything I had ever heard.  Heck, it sounded better than most live concerts I had been to and all this in someone’s living room with ancient tubes powering it.  I was stunned.  I was hooked.

And here I am today.