Automotive History: Delco-GM/Bose Sound System – GM’s Greatest Hit Of The 1980s

The terms “General Motors” and “Innovation” aren’t often used together when referring to the 1980s.  Successes were rare for GM during this period, and its US market share plummeted from 44% to 35%… but among the company’s achievements was a product that almost immediately changed how carmakers approached sound systems.  Innovative and trend-setting, the Delco-GM/Bose Sound System was the kind of product that most companies can only dream about developing.  And this was all made possible by a seemingly unlikely corporate alliance that endures to this day.

Introduced for the 1983 model year, the Delco/Bose sound system was the right product at the right time, as it capitalized on a crescendo of interest in auto sound that had been building for decades.  The partnership that led to this innovation was an unlikely one.  Behemoth General Motors, struggling in the fast-paced 1980s not to sink under its own weight and inertia… and 18-year old Bose Corporation, a small company that became a celebrated name in high fidelity by swimming against conventional wisdom.  However odd the alliance may seem, this first mass-market collaboration between a carmaker and the audio industry changed the field of auto sound almost overnight.  Prior to Delco/Bose, customers needed to install aftermarket systems in their cars to get first-rate sound; within just a few years, other manufacturers were chasing GM’s lead.

Motorola was an early leader in car radios – the name itself is a contraction of “Motor” and “Victrola”


Music and driving have always been complementary.  Automobile radio became widely available in the 1930s, and the indulgence of listening-while-driving gradually trickled through the car market over the next several decades.  But actual high fidelity was elusive, since cars – small, oddly-shaped enclosures surrounded by glass, metal, plastics and fabric – hardly lent themselves to acoustical perfection.  People accepted sound distortion as a fact of life.

General Motors started developing radios in the 1930s, and had a captive company to do the work.  Delco (originally Dayton Engineering Laboratories Company) had been manufacturing automotive componentry since 1909, and was acquired by GM in 1918.  Delco became familiar to customers as a brand of everything from batteries to shock absorbers, but it’s radios that are relevant to today’s story.  Delco was synonymous with radios in GM cars, which were often quality examples of auto sound in any given decade.  Delco’s size and diversity of products provided unsurpassed economies of scale and expertise in electronics.  For example, by the 1980s Delco Electronics was the world’s third-largest manufacturer of integrated circuits (a crucial ingredient of modern sound systems), behind only IBM and Western Electric.

Bose Corporation had much different beginnings.  Philadelphia-born MIT professor Amar Bose grew frustrated with the poor sound quality of home audio speakers, so in 1964, at age 35, he founded his own company.  His breakthrough came just four years later with the Bose 901 loudspeaker, different from other speakers of its time in every significant way.  Most notably, it was a “direct/reflecting” speaker – meaning that much of the sound output was intended to be reflected off of walls, rather than aimed directly at the listener’s ears.  In fact, each 901 speaker contained nine drivers – eight of which were aimed at walls.

The holy grail of home hi-fi systems was to replicate the sound of a concert hall.  Yet Dr. Bose grasped that in actual concert halls, most of the sound that reaches the audience is reflected off walls and other surfaces.  Bose’s speakers mimicked that pattern of sound propagation – and did so to critical acclaim.  Among the 901’s benefits was that the speaker created a more “spacious” sound – making the listening room seem larger and the sound more realistic.  Unbeknownst to anyone at the time, the same theory held the promise to better car audio sound as well, but that was years in the future.

While the 1960s was the decade when home audio systems saw fantastic sales growth, for car audio, it was the 1970s.  Cars got quieter, pre-recorded portable music (8-tracks and cassettes) became readily available, and old-style single-speaker radios were suddenly antiquated.  But factory-installed audio systems were usually viewed as having poor sound quality.  Consequently, the aftermarket auto sound industry grew… and grew… and grew.

Car stereo shops seemed to sprout up in every town, and by the early 1980s, US aftermarket car stereos formed a $2 billion per year industry.  Many consumers would eschew factory audio options altogether in favor of more feature-laden aftermarket systems; in 1980, 17% of domestic cars and two-thirds of imports were sold without any kind of radio, and nearly two-thirds of all car buyers purchased some sort of aftermarket audio components.

Carmakers felt cut out of an increasingly lucrative game.  Some manufacturers responded by offering a dizzying array of radio options (for instance, Ford’s 1982 LTD Crown Victoria offered nine different sound systems); yet many customers still chose aftermarket receivers and speakers for better sound quality.

Bose Corporation entered the auto sound fray in 1980, when the company debuted a receiver and speaker combination called the 1401.  As one might expect from the company that pioneered direct/reflecting home audio technology, the 1401’s setup bore some similarities to Bose’s iconic 901 speakers.  Specifically, the rear speakers were aimed towards the rear window, thus reflecting sound forward.  The 1401 also featured active equalization (to provide optimal tonal balance), again similar to Bose home audio systems.  With four 25-watt amplifiers and excellent speakers, this was an advanced system for its day, however Bose’s first foray into car audio was not a commercial success.  Its significance is more apparent in retrospect: This was essentially a beta version of what would come about two years later – the Delco-GM/Bose system.

The story of our featured sound system began in 1979, when Dr. Bose himself approached Delco Electronics to discuss a potential collaboration between the two companies.  In a process more reminiscent of the 1920s than the 1970s, the deal was consummated with a handshake – three years and $12 million of R&D followed (and eventually a formal contract, signed in 1982).

The goal was to provide Bose speakers customized for GM’s E/K-body cars – the Cadillac Seville and Eldorado, Buick Riviera and Oldsmobile Toronado, which were the flagships of their respective divisions.  With these cars, Delco and Bose could find buyers with enough income to consider a high-dollar sound system, and the cars themselves had the luxury-car ambiance that would invite those buyers to listen to good music.  Plus, the cars’ relatively spacious designs offered Bose sufficient options for speaker placement (Fisher Body also participated in the development process).

Much of this sound system’s innovation revolved around the Bose speakers, and the central character of many Delco/Bose ads was a red-faced mannequin nicknamed Morgan.  Ads described how Morgan had microphones for ears, and that he helped “match the system components to the individual car.”  This was not a marketing gimmick – Morgan really did hold the key to the system’s development.

Morgan was positioned in various seating positions of each E- and K-body model at Delco’s Indiana research facility.  Throughout the R&D process, the mannequin’s ear-microphones recorded sounds from the under-development audio equipment, and this information was then transmitted to Bose’s Massachusetts headquarters.  Acoustical engineers then used this data to develop the sound system’s most innovative aspect – speakers with a novel sound radiation pattern.

Bose considered the optimal placement for front speakers to be in the lower door panels.  But speaker placement accounts for only part of this system’s success.  In most 1980s car stereo systems, a driver or passenger would mostly hear sound coming from the nearest speaker, meaning that any kind of genuine stereo effect was lost – and no amount of fiddling with balance controls could compensate for that.  Bose’s solution was to aim most of the output from the front passenger-side speaker towards the driver (and vice-versa).  This process, following a theory called sound imaging, effectively tricked the listeners’ ears into perceiving that a given sound source was located somewhere else.  In this case, Bose adjusted speaker output so that both driver and passenger were treated to an acoustical “sweet spot,” and this was possible because the mannequin-head microphones directed Bose engineers to the precise placement and output to provide the effect of perfect stereo.  Such “psychoacoustics” achieved a true stereo perspective that was missing from all other car-audio setups of the day.

Each of the system’s four speaker modules contained its own 25-watt two-state amplifier, a 4” helical voice coil wide-range drive unit, and a vented enclosure.  Modules were surrounded by foam and fiberglass in order to minimize distortion and unwanted resonance.  Interestingly for the era, there were no tweeters or woofers, and the four small-but-powerful amplifiers provided a combined 100 watts in an unconventional way (instead of the more common single trunk-mounted amp).  But every unconventional aspect of this system had a purpose.  The individual amps, for instance, enabled Bose to better adjust the spatial control circuitry, which was essential to the system’s success.

Source: Stereo Review, June, 1983.


This was the first audio system custom-tailored to specific cars, a process that was mind-numbingly complex, as illustrated by a story told by Joe Veranth, Bose’s vice president of engineering.  As one of the engineering team’s goals was to provide a relatively flat frequency response at all seating positions, equalization had to be precisely adjusted.  One would assume that the all-important acoustical “equalization curves” for the three E-body coupes would be similar, since the cars were nearly carbon copies of each other.  But surprisingly, Bose engineers measured equalization curves that differed by as much as 12 dB.  Veranth attributed this variance to almost imperceptible differences in the cars’ rear parcel shelves and other minor trim changes.  In acoustical engineering, even minute variations in a listening environment can alter how sounds are heard, so the sound system had to be adjusted differently for all three E-body coupes.

Oldsmobile Toronado door panel with Bose speaker


A relentless exercise of moving and adjusting the speakers continued late in the development process, as one small adjustment in something like circuitry or equalization would shift the speakers’ directional characteristics.  For example, GM wanted speaker grille material to match the door fabric, which necessitated another round of adjusting the equalization, which in turn affected the optimal speaker placement.  Thus, it’s little wonder that it took three years to design a car stereo.

But this work paid off.  Automotive and audiophile journalists were invited to preview the final results shortly before the 1983 models hit showrooms.  It’s impossible to find a review of this system that’s not amazingly enthusiastic.  For example, Stereo Review’s editor wrote “I didn’t know how good the sound in a car could be until I heard the Delco-GM/Bose Music System.”  Prominent consumer electronics expert Leonard Feldman said “It’s as good or better than the best home systems I’ve heard.”  Road & Track’s reviewer raved about the system, despite his “best efforts to dislike, distrust, and generally poke holes” in anything sold by General Motors.

The sound from one of these systems was balanced, smooth and deep – with a luxurious sound that matched that of high-quality home audio systems of the day.  Simply put, this produced the richest sound imaginable from a car stereo – and that it was from a factory-installed unit was simply remarkable.

It was also very simple to use.  The receivers themselves looked rather ordinary, despite the fact that this was the most complex car stereo of its day.  There was no graphic equalizer (since equalization was done electronically) and no left-right balance control (due to the complex sound imaging) – no unnecessary controls to distract the driver.  Just turn it on, and enjoy.  And since it was factory installed, the overall appearance was well-coordinated with the cars’ interior design (the aforementioned upholstered speaker grilles looked much better than often-unsightly aftermarket speakers).

For 1983, the Delco-GM/Bose sound system was offered as an $895 option on the E/K-body cars, and later on the 1984 Corvette.

While its quality was unquestioned, no one knew whether customers would spring for an $895 factory sound system.  On one hand, this appeared as somewhat of a bargain, since mid-grade sound systems from companies such as Kenwood, Marantz or Sanyo typically retailed between $300 and $600, and very high-end receivers such as the Blaupunkt Berlin 8000 cost well over $1,000… not including installation.  However, $895 was still a hefty sum, and the market for high-end factory-supplied systems was untested.  Given that, the E/K-body cars were a good place to start.  Relatively high sticker prices (most Eldorados & Sevilles sold in the mid-$20,000 range, while Rivieras and Toronados cost less) meant that the option stayed under 5% of the total purchase price.

Source: Wall Street Journal, Aug. 29, 1983


Initial sales expectations were modest, with GM predicting between 10-15% of E/K-body buyers would choose the Delco/Bose option.  However, during 1983, nearly a quarter of Seville/Eldorado buyers chose it, 20% of Toronado buyers, and 15% of Riviera buyers.  When the option was extended to the ’84 Corvette, the early take rate was a startling 81%.  With those numbers, the concept proved to be a success.

Success meant that GM could move ahead with greater availability.  By 1985 the option was extended to GM C-body cars (i.e., Buick Electra), and from there quickly filtered down through more of the company’s vast model range.  The Delco-GM/Bose system was incrementally improved with each new model, but the core concept stayed the same, and continued to receive outstanding reviews.

For General Motors, its affiliation with Bose was a much-needed success in what otherwise was a brutal decade.  In fact, since that time, GM has been at or near the top of auto sound among major manufacturers.  And the Bose partnership continues to this day – while the number of speakers and features have grown, the same premise of customization that created outstanding sound in Sevilles and Rivieras continues to succeed in Escalades and Enclaves.

Even more significantly, this system had a profound effect on the overall car market.  Within just five years, Ford had partnered with JBL; Chrysler with Infinity; and Nissan, Acura and Audi with Bose (whose GM contract wasn’t exclusive).  Among all manufacturers, sound systems quit being an afterthought, and instead became a significant selling point.  By the end of the decade, the proportion of new US cars sold without radios plummeted to near zero, and the average car of 1990 had a better sound system than even most costly cars from the pre-Delco/Bose era.

The Delco-GM/Bose sound system created reverberations throughout both the auto and audio industries… it’s tough to think of an automotive component that so quickly changed consumer products.  Bose’s expertise, along with General Motors’ production capabilities, created a unique partnership.  This was the right product, at the right time, developed by the right companies.  And the next time you think that GM was completely moribund in the 1980s, just turn up the volume and enjoy the significance of one of The General’s greatest hits.