Koss Corporation founder John Koss shares his behind-the-scenes story of inventing the world's first SP/3 stereophone in 1958, and the emotional thrill of being "enclosed in the music" thanks to his innovation.
- History Timeline:
Founded 1958
World's First SP/3 Stereophone
In 1958, John C. Koss teamed up with engineer Martin Lange, Jr. to develop a portable stereo phonograph player with side-wing speakers. The pair demonstrated their new stereo record player at a Wisconsin audio show. One of the product's unique features was a privacy switch, which allowed listeners to hear music by plugging in the world's first SP/3 stereophone. The stereophones were intended to be an accessory to deomonstrate the high-fidelity stereo sound that the portable phonograph player delivered.
The revolutionary sound of the Koss SP/3 stereophone became the hit of the show.
1958
SP/3
The World's First Koss Stereophone
In 1958, John C. Koss invented personal listening with the world’s first SP/3 stereophone. Koss sought to replicate the excitement of a live musical performance. The original SP/3 stereophone allowed listeners to experience sound as they had never before, bringing them closer to the music they love.
1962
PRO/4
1960
SP/3X
1966
Frank Sinatra Jr.
1966
Bobby Hackett & Tony Bennett
1968
ESP/6
In 1968, Koss released the ESP/6, the world’s first self-energizing electrostatic headphone. To achieve its unprecedented sound profile, the ESP/6 employed the principle of a currentless, or electrostatic charge. The charge was applied to push-pull condenser plates, and caused movement of an ultra lightweight conductive diaphragm.
1969
Air Force One Outfitted With Koss Stereophones.
In 1969, passengers aboard Air Force One were treated to the Sound of Koss. The Presidential Plane’s state-of-the-art entertainment system featured Koss headphones at every seat - including the staff, press, and presidential quarters. About 50 Pro/4 units in total lined the aircraft.
1970
Pete Fountain
1969
ESP/7
1970
Pro/4AA
In 1970, Koss set the standard for full-size professional headphones with the iconic Pro/4AA. At the time of their introduction, the Pro/4AA were regarded as the first dynamic headphones to deliver true full frequency and high fidelity performance with impressive noise-isolating capabilities.
1970
Koss World Headquarters moves to 4129 North Port Washington Ave, Milwaukee, WI 53212
1972
Koss enters the U.S. Smithsonian. John C. Koss is shown here with the original Koss SP/3.
1972
Ever Wonder Why He's Smiling
1973
Mel Torme
1974
Doc Severinsen
Doc Severinsen, personality director for Johnny Carson's "Tonight Show," signs as the official Koss spokesman.
1974
HV/1A
In 1974, Koss released the HV/1A. The first dynamic headphone capable of reproducing all 10 audible octaves, the HV/1A paved a new course in personal listening. The unmatched sound, and modern dynamic speaker elements found in Koss Headphones today are a direct evolution from the legendary HV/1A.
1974
Give Your Neighbors the Silent Treatment
1974
Hear No Evil
1974
Not All Stereophones are Created Equal
1975
K/7
1975
Easy Listener
1975
Live and Let Live
1976
Pro/4AAA
In 1976, Koss introduced the Pro/4AAA. Building off of the Pro/4AA’s iconic sound, the Pro/4AAA incorporated a number of new design features. The most notable of these features was the headphone’s Direct Contour Pneumalite ear cushions. The shape of the cushions mirrored an ear’s natural “D” shape. This advancement in design informed the very pronounced “D” Profile found in many Koss headphones today.
1977
King Koss
1977
Lettuce Entertain You
1978
Have You Had a Koss Encounter?
1978
Think Koss
1979
John C. Koss inducted into the Audio Hall of Fame.
1980
Fortunate Cookie
1980
Ski Koss Country
1981
John C. Koss tours the Koss Factory floor.
1982
Medical College of Wisconsin
Koss endows Medical College of Wisconsin to establish Koss Auditory Center for Research and Treatment.
1982
Stereo to Go
1984
Porta Pro
In 1984, the acclaimed Koss Porta Pro set performance and comfort standards for portable personal listening - worldwide. Designed for those with a refined ear for music, the Porta Pro continues to be one of the most popular headphones around the world.
1986
Santa Kossing
1987
Noah's Favorite Pair
1987
Phone Your Mother
1987
JCK/100
1987
HV/1A+
1988
Koss Billboard in 1988.
1989
JCK/300 Kordless Stereophone System
In 1989, the Koss JCK/300 cordless headphone set the standard for infrared wireless headphones. By developing a new transmitter that delivered four times more power than conventional infrared headphone systems, Koss cut the cord and changed personal listening forever.
1989
Wrap Music
1990
ESP950
In 1990, Koss introduced the revolutionary ESP/950 electrostatic headphone. The ESP/950’s breakthrough design incorporated electrostatic transducers with ideal mechanical damping. The unit’s distortionless sound is attributed largely to its ultra-thin (1.5 micron) diaphragms. Each diaphragm moves uniformly thanks to an electron deposited proprietary semi-conductive coating.
1991
"Music Lovers of the World Unite." Advertisement.
1990
Founder John C. Koss with sons Michael J. Koss and John Koss Jr. From generation to generation, Koss continues to bring you closer to the music you love.
1995
KSC35
1992
Pro4XTC
1995
Tchaikossky
2000
Introduction into the Consumer Electronics Hall of Fame
In 1958, John C. Koss teamed up with engineer Martin Lange, Jr. to develop a portable stereo phonograph player with side-wing speakers. The pair demonstrated their new stereo record player at a Wisconsin audio show. One of the product's unique features was a privacy switch, which allowed listeners to hear music by plugging in the world's first Koss SP/3 stereophone. The stereo-phones were intended to be an accessory to deomonstrate the high-fidelity stereo sound that the portable phonograph player delivered.
John C. Koss Sr. is inducted into the inaugural class of the Consumer Electronics Hall of Fame. At the dawn of the transistor era, John Koss Sr. designed a set of commercial headphones using World War II military headphones. It was 1958 and the stereo business was taking off with the advent of rock'n'roll music. The headphones were called "private listening units".
This award is in recognition of John Koss Sr's. contribution and pioneering spirit that have laid the foundation of consumer electronics.
2002
When Your True Love is Music
2002
UR40
2002
KTXPro1
2004
John C. Koss inducted into the Wisconsin Business Hall of Fame.
2004
Party Favorites
2004
Head of the Class
2005
Rock of Ages
2005
The Pair to Beat a Full House
2009
Koss Training
2012
Striva Tap
2012
Striva Pro
2013
KSC32 FitClips
2013
KEB32 FitBuds
2013
Koss Stereophones became a recurring client of Sterling Cooper on the Emmy winning show "Mad Men".
2013
No Brainer
2014
BT540i
In 2014, Koss once again cut the cord with the BT540i wireless Bluetooth® headphone. A technological powerhouse, the BT540i incorporated a state-of-the-art Bluetooth chip, NFC® one-touch pairing, and near-lossless sound with aptX® codec.
2014
BTS1
Small enough to fit in a pocket and weighing just 0.36 lbs, the BTS1 Wireless Bluetooth® Speaker is designed specifically for portability and on-the-go use.
2014
Pro4s
Carrying on the legacy of the Pro/4 line, 2014’s Pro4S studio headphone was specifically crafted for audio professionals. Featuring the all-new SLX40 element, and iconic “D” Profile shape, the Pro4S delivers remarkably accurate sound.
SP Series
Introduced in 2014, the SP540 and SP330 both feature Koss’ iconic “D-profile” earcup design. The “D-profile” mimics the shape of the ear, creating an ideal seal for the most consistent sound reproduction, and an incredibly natural fit. Optimized PLX40 and PLX30 dynamic elements deliver an unmatched personal listening experience.
2017
Kossfit
2016
Gladmen
2016
Game of Phones
2017
BT539i
Introduced in 2017, Koss would continue expanding its Wireless Bluetooth® line of over-ear headphones with the BT539i. The Koss BT539i Wireless Bluetooth® Headphones have the natural fitting, iconic "D-profile" earcup, first featured on the ergonomically designed Koss Pro4AAA and now available on many Koss headphones.
2017
KPH30i
The Koss KPH30i is a direct descendant of the Koss Pro35 and popular Koss KTXPro1. With all-new modern features like an in-line microphone and remote, the KPH30i keeps listeners connected all while enjoying their favorite tunes. The lightweight on-ear headphones feature an open-air design with smooth bass and clean treble. The 60-ohm elements are perfectly tuned for use on the go with most mobile hardware content players.
2017
GMR-540-ISO Closed-Back Gaming Headphones
2017
GMR-545-AIR Open-Back Gaming Headphones
2018
Porta Pro® Wireless
In 2018, Koss brought the legendary sound and design of the iconic Porta Pro®, that music lovers have been enjoying since 1984, into the 21st century with modern features—like Wireless Bluetooth®, in-line microphone and on-board controls—all while keeping the iconic sound, comfort and design intact.
2018
Noise Canceling QZ Buds
The Koss Quiet Zone QZBuds In-Ear Noise Cancellation Earbud Headphones are designed to cancel-out unwanted, annoying noises allowing listeners to relax and focus on what matters. The Koss Quiet Zone QZBuds In-Ear Noise Cancellation Earbud Headphones feature a monitor mode button that can be activated to allow users to hear what's going on around them so they never have to remove their headphones.
2018
CS300 Communication Headset
Available in single-sided or double-sided versions, the Koss Headphones CS300 Communication Headset features USB connection and flexible boom microphone with the noise-cancelling electret microphone. Combined with its lightweight design, unique Koss D-Profile with soft, pillow-like cushions, the CS300 Communication headsets combine ease of use with all-day comfort in a single, stylish headset perfect for the office, call centers and video conferencing.
2019
Still Inventing After All These Ears
2019 marked 60 years since the invention of the World's First SP/3 Stereophone by John C. Koss. Koss celebrated this monumental moment with a double-sided billboard near their World Headquarters in Milwaukee, WI, USA showcasing the SP/3 on one side, and the upcoming A/550 on the other.
2021
Koss Utility Series
Koss Utility Series introduces three new headphones KPH40 Utility, KEB90 Utility and Porta Pro® Utility all featuring a detachable cord system that gives listeners the freedom and flexibility to connect to virtually any device they own now, or in the future.
2023
True Wireless Earbuds & Wireless Noise Cancelling Headphones
In 2023 Koss continued expanding its Wireless Bluetooth® line of earbuds and over-ear headphones with the TWS250i True Wireless Earbuds and BT740i QZ Wireless Active Noise Cancelling Headphones.
2024
Porta Pro Wireless
In 2024, Koss celebrated the 40th anniversary of the acclaimed Porta Pro headphones. Originally introduced in 1984, Porta Pro set a new standard in personal, portable audio with its groundbreaking design. Porta Pro Wireless continues this legacy, combining its innovative dual steel headband with Bluetooth technology to deliver the same legendary sound that listeners have come to love, while preserving the iconic comfort, portability, and durability that has defined Porta Pro for forty years.
2024
Time Tested
In 1984, John C. Koss unveiled the Koss Porta Pro, a headphone that would revolutionize personal portable audio for decades and become one of the most iconic and enduring headphones in audio history. In 2024, Koss celebrated the 40th anniversary of this legendary headphone with the launch of the next-generation Porta Pro Wireless, highlighted by a double-sided, retro-themed billboard near the company's world headquarters in Milwaukee, WI. This special installation paid homage to the original design and legacy of the Porta Pro, while introducing a modern evolution of its beloved sound and style.
2025
KPH30 Wireless
Reimagined from the inside out, the Koss KPH30 Wireless features breathtaking high-fidelity audio from 15-20,000 Hz. Built on an all-new, sophisticated design that stays true to the original KPH30i aesthetic, KPH30 Wireless introduces a redesigned headband and Patent Pending suspension built for increased strength, durability, and all-day comfort
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