Rest in Peace. The Wizard of Foz
Fosgate invented the first car audio amplifier in 1973, with his company; Fosgate Electronics which became Rockford Fosgate.
Millions owe it to him the legacy and legitimacy of aftermarket Car Audio.
https://en.wikipedia.org/wiki/Jim_Fosgate
https://www.tnt-audio.com/intervis/fosgate_e.html
Fosgate invented the first car audio amplifier in 1973, with his company; Fosgate Electronics which became Rockford Fosgate.
Millions owe it to him the legacy and legitimacy of aftermarket Car Audio.
https://en.wikipedia.org/wiki/Jim_Fosgate
https://www.tnt-audio.com/intervis/fosgate_e.html
I only owned one of his products over the years. I don't remember the exact model, but I will say that it had to do with a wider stereo image, some bass compensation, and was variable. Getting to the point, I always take the top of any unit that I buy just to see what might be upgraded. In this case, there was absolutely nothing inside that could be bettered! A rare occurrence for me.
He also did lots of audio related engineering outside of the car audio sphere. Apparently a pretty down to earth fellow. RIP Jim Fosgate.
RIP Jim... I read he had quite a collection of vintage audio equipment, some kept just because he liked the particular circuit inside. He would have been a fascinating fellow to hang with for a day!
My first legit car stereo had a 1st gen Punch 45, thing was tuff as nails. Good times car audio was in the 80's!
I remember Summertime cruising to the River or Lake in my Geo Metro.
With my Girlfriend and her friends.
2x12" subs powered by a Punch Amplifier . The most reliable
Car amp I owned.
For being such a Nerdy Car, The Girls absolutely loved it !
Some of the best memories of my life singing and laughing in that car.
Deep Bass and 50 Miles to the Gallon. Good Job Jim !
With my Girlfriend and her friends.
2x12" subs powered by a Punch Amplifier . The most reliable
Car amp I owned.
For being such a Nerdy Car, The Girls absolutely loved it !
Some of the best memories of my life singing and laughing in that car.
Deep Bass and 50 Miles to the Gallon. Good Job Jim !
He was definitely a pioneer but there are some qualifiers on that. Mobile amplifiers existed long before Jim Fosgate entered the market as did car specific ones. Didn't he develop the 1st reliable switching supply for mobile use in an amplifier?
Something comparable would be the Operational Amplifier and Feedback amplifiers. It was nothing new and plenty of examples dating
back to the 30's and 40's even tube based op amps. And even the original Bell Labs patents.
But for most of us, history of Op Amps starts with Fairchild when the LM101 was updated to uA741
very much the most popular and commercially successful OpAmp.
Far as Mobile Audio, Similar Story.
Plenty of tube based and solid state examples prior to Fosgate.
But yes as far as boosted rails and high power applications.
The History of Car Audio starts with Jim Fosgate. As the most successful modern mobile audio innovator.
What most consider now typical Car amplifiers, did not exist till he created the concept
The initial concept a Equalizer, then powered Equalizer , Then the well known case style and heatsinks used for car audio amplifiers.
With boosted rail supply's way above the available 12 volt system
Which also revolutionized what speaker manufactures started to offer for car audio.
Since more power was available you were not limited to stiff suspension high sensitivity, high distortion speakers.
You could use more " Hi Fi" speakers with better sound quality. Since higher power was more feasible.
Which spawned the larger loose suspension more HiFi sound quality 2 way and 3 way speakers now common in
car audio
Cerwin Vega already known for bringing " earthquake" 18" Subwoofers to the theater
Quickly caught on and developed numerous 10" 12" and 15" subwoofers designed for car audio
since it was now feasible to do with high power mobile amplifiers.
Anybody will tell you from early car audio days. If you wanted high quality sound.
You needed a " EQ" basically a EQ which also had a higher power amplifier than a stock radio.
Which is what you were really after, the amplifier. The EQ part just a added benefit.
Then moved on to the modern heatsink/ case style we are familiar with for even higher power.
Again anybody from early days will tell you. The formula was simple. A Rockford Fosgate car amplifier
and a Cerwin Vega Subwoofer. Many still using the original concept. The " EQ" and built in power
amp powered the Hi Fi door speakers. Then another even larger amplifier was used to power the Subs.
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Seems HISTORY here overlooks Dr Gerhard Gunther of A/D/S/ Fame. A/D/S/ INTRODUCED the Autosound industry to the DC-DC Switch Mode power source, the power source ALL OTHERS would use/duplicate in their amplifier designs. That's HISTORY
Dr Guenther came to America from Germany at the request of Wherner Von Braun, the rocket scientist who was working at NASA. In 1968 Dr Guenther came to America and began a stint at NASA that would eventually result in the DC-DC power system, created for satellite use. About 1970, the Doctor decided to bring this creation to market in the form of a HIGH POWER AMPLIFIER system for Automobiles. In 1972 with money and designs in hand and a scheme to raise more capital selling transshipped European speaker components, the Doctor started the A/D/S/ Corporation.
Early in 1973 production would ensue on his flagship product... the A/D/S/ 2001 Amplifier and Speaker system. Officially released in 1974, this system composed of a 160 watt BI AMP power amp and a solid aluminum constructed speaker system utilizing the very first "super woofer" in history as well as the world class A/D/S/ tweeter system. These systems were on the streets in 1973 as I recall pulling one out of a 74 Mercedes. Story was it was a "gift" from the Doctor himself in 1973. I pulled it in 1983... a 10 year run, swapped it out for a Jensen Bi Amp job from them times. Speakers still sounded great.
In the summer of 1975 the A/D/S/ corporation was featured in AUDIO magazine on the front cover. The A/D/S/ 2001 TRUE AUDIOPHILE Autosound system, available in over 1200 stores nationwide and in Canada had hit the magazines of them times. Full Spread. Thats HISTORY.
SO, we all know now that it was the Doctor... the A/D/S/ corporation, that INTRODUCED the DC-DC Switch Mode Power System to the Autosound Amplifier world as NOTED in THEIR OFFICIAL literature of them times. Just so ya all know, Ol Jim there got "his" ideas.... from somewhere. Look into this... Historical TIMELINE issue... PROPS to the Doctor that started it ALL... and took very little credit for it.... in writing.
NJOY/BDBD/2023
Dr Guenther came to America from Germany at the request of Wherner Von Braun, the rocket scientist who was working at NASA. In 1968 Dr Guenther came to America and began a stint at NASA that would eventually result in the DC-DC power system, created for satellite use. About 1970, the Doctor decided to bring this creation to market in the form of a HIGH POWER AMPLIFIER system for Automobiles. In 1972 with money and designs in hand and a scheme to raise more capital selling transshipped European speaker components, the Doctor started the A/D/S/ Corporation.
Early in 1973 production would ensue on his flagship product... the A/D/S/ 2001 Amplifier and Speaker system. Officially released in 1974, this system composed of a 160 watt BI AMP power amp and a solid aluminum constructed speaker system utilizing the very first "super woofer" in history as well as the world class A/D/S/ tweeter system. These systems were on the streets in 1973 as I recall pulling one out of a 74 Mercedes. Story was it was a "gift" from the Doctor himself in 1973. I pulled it in 1983... a 10 year run, swapped it out for a Jensen Bi Amp job from them times. Speakers still sounded great.
In the summer of 1975 the A/D/S/ corporation was featured in AUDIO magazine on the front cover. The A/D/S/ 2001 TRUE AUDIOPHILE Autosound system, available in over 1200 stores nationwide and in Canada had hit the magazines of them times. Full Spread. Thats HISTORY.
SO, we all know now that it was the Doctor... the A/D/S/ corporation, that INTRODUCED the DC-DC Switch Mode Power System to the Autosound Amplifier world as NOTED in THEIR OFFICIAL literature of them times. Just so ya all know, Ol Jim there got "his" ideas.... from somewhere. Look into this... Historical TIMELINE issue... PROPS to the Doctor that started it ALL... and took very little credit for it.... in writing.
NJOY/BDBD/2023
Attachments
I had the system in the fourth picture in my convertible mgb and someone cut it open and stole it. i was 19 and I almost cried.
I have some history from around that time too. My father had a gizmo by which he could run his electric razor and shave on the way to work. It had a mechanical vibrator in it; 12VDC in 110 out. He'd given up on the idea, so, as a teenager I took the device for the step-up transformer.
Looking at schematics for multivibrator circuits, appearing as two cross-coupled transistors, I took a couple of transistors we had, put them on heatsinks and connected them to the transformer. I believe I was inspired by a Radio Shack device you could buy at the time.
I connected the bases of the transistors through a resistor, to the opposite side, roughly following the schematic I found. Whatever powers that be must've really wanted me to pursue this, as instead of smoke, it oscillated when I turned it on. At close to 60Hz too; just two transistors, two resistors and that transformer. I put it in a wood box, with a meter that read the voltage output.
One day we put my whole system into a friend's van, which consisted of a TEAC tape deck, a small Electrovoice reveiver and my speakers, as it was still fairly unusual at the time to be able to listen to your own recorded music in a car. It worked with one caveat; the frequency would change with input voltage. Literally, the song playing would slow down going uphill - and speed up going downhill in this Ford van.
At the park where we were headed, we set everything up at some pavillion with AC. Enjoyed our music on a beautiful summers day. Someone cut the AC being delivered to that pavillion. I'm pretty sure to their amazement, we had the music playing again in about 5 minutes, using my inverter. It wouldnt play as loud as when powered by the AC line, but play it did.
As thanks to the powers that be granting me early success just because I tried to do it one time, I never did anything further with it. Didnt pursure circuits that could stabilize the frequency, didnt pursue transformers / transistors that could deliver more power.
Looking at schematics for multivibrator circuits, appearing as two cross-coupled transistors, I took a couple of transistors we had, put them on heatsinks and connected them to the transformer. I believe I was inspired by a Radio Shack device you could buy at the time.
I connected the bases of the transistors through a resistor, to the opposite side, roughly following the schematic I found. Whatever powers that be must've really wanted me to pursue this, as instead of smoke, it oscillated when I turned it on. At close to 60Hz too; just two transistors, two resistors and that transformer. I put it in a wood box, with a meter that read the voltage output.
One day we put my whole system into a friend's van, which consisted of a TEAC tape deck, a small Electrovoice reveiver and my speakers, as it was still fairly unusual at the time to be able to listen to your own recorded music in a car. It worked with one caveat; the frequency would change with input voltage. Literally, the song playing would slow down going uphill - and speed up going downhill in this Ford van.
At the park where we were headed, we set everything up at some pavillion with AC. Enjoyed our music on a beautiful summers day. Someone cut the AC being delivered to that pavillion. I'm pretty sure to their amazement, we had the music playing again in about 5 minutes, using my inverter. It wouldnt play as loud as when powered by the AC line, but play it did.
As thanks to the powers that be granting me early success just because I tried to do it one time, I never did anything further with it. Didnt pursure circuits that could stabilize the frequency, didnt pursue transformers / transistors that could deliver more power.
They were something that I certainly noticed and was curious about as a kid. I didnt have the clarity to see that you could trade current for voltage to get a higher power amp going in a car - and skip the 110V conversion. At about the same time, I'd built 1 channel of a 20W Tiger amp - just for bass - and ordered the tranfo, diodes, cap and wired it all up, but couldnt see the "if I can only get 30V from 12 somehow" step to do better than BTL outputs at ~12V p-p.