ADC Accutrac +6 (1976–1979)
The turntable that promised a robot butler for your record collection, and almost delivered.
Overview
The ADC Accutrac +6 is pure 1970s optimism. It didn't just play records, it was supposed to *think* about them. Stack six albums, program your favorite tracks with a mushroom-shaped infrared remote, and let the machine sort out the rest. For 1976, that was close to magic. It wasn't a stripped-down changer for background music. It was a statement piece, aimed at the buyer who wanted their stereo to *do things*. Where the execution lagged behind the ambition, that's part of the charm now.
BSR, a British manufacturer, built the +6 for American brand ADC (Audio Dynamis Corporation). It was the evolution of the Accutrac 4000. The 4000 had the glowing orb remote receiver and single-play precision. The +6 added a six-record changer, hence the name, and kept the same infrared control system. It wasn't a flagship in the traditional sense. It carved out a niche as the "smart" changer, a bridge between audiophile aspirations and living-room convenience. It sat above basic changers from Voice of Music or RCA, but below true high-end manual turntables. The target buyer wanted automation without giving up too much fidelity.
The +6 used a belt-drive system with a two-speed platter (33⅓ and 45 RPM). Direct-drive tech was emerging from Japan at the time, and this was a far cry from it. The tonearm was a static-balance S-shaped design, decoupled to reduce resonance. It came standard with ADC's LMA1 cartridge, a low-mass, high-output moving magnet with an elliptical stylus. That cartridge was no afterthought. It tracked well for its era and could extract decent detail from vinyl, provided the system was set up properly. The real novelty was the track selection logic. Using optical sensors and a memory bank, it could skip to specific tracks on each record, which felt like science fiction in the mid-70s. You could program it to play track 3 from record one, then jump to track 1 on record four. No other changer offered that at the time.
Still, this was a record changer. The mechanism was clever, but it lifted and lowered multiple records via a concentric spindle and a rising platform that minimized drop distance. It worked, often impressively, but it wasn't silent and it wasn't fast. The clunks, whirs and soft thuds as the machine cycled through records were just part of the show back then. And like all changers, it demanded care. Warped records could jam the system, and dust buildup in the spindle mechanism could cause misfeeds.
Specifications
| Manufacturer | ADC (Audio Dynamis Corporation), manufactured by BSR |
| Production Years | 1976–1979 |
| Model Number | 3500/1-RVC |
| Turntable Type | Belt-drive, automatic, six-record changer |
| Speeds | 33⅓, 45 RPM |
| Platter | Aluminum alloy, dynamically balanced |
| Tonearm Type | S-shaped, static balance, decoupled counterweight |
| Effective Length | 237 mm |
| Overhang | 15 mm |
| Offset Angle | 21° |
| Cartridge | ADC LMA1 (moving magnet) |
| Output | 3.5 mV at 5.5 cm/s |
| Stylus Type | Elliptical diamond (0.0003" x 0.0007") |
| Tracking Force Range | 0.75–1.5 grams |
| Frequency Response | 10 Hz – 24 kHz (±2 dB) |
| Channel Separation | 28 dB |
| Wow and Flutter | < 0.03% (DIN 45507) |
| Rumble | –70 dB (DIN 45539B), –50 dB (DIN 45539A) |
| Remote Control | Infrared, mushroom-shaped receiver, model TX-1 |
| Dimensions | 470 x 441 x 152 mm |
| Weight | 9 kg |
Key Features
The Mushroom That Listened
The +6 didn’t just come with a remote—it came with a *character*. The infrared receiver, a bulbous, translucent “mushroom” perched on a stalk, became an icon of 1970s tech whimsy. It wasn’t just for show: the unit used optical sensors to detect commands from the handheld remote, allowing full control over track selection, play, pause, and record changing without touching the turntable. The receiver had a confirming LED that flashed when a command was received, giving instant feedback in an era when most electronics offered none. Owners report that the system was surprisingly reliable, though line-of-sight was essential, and sunlight could sometimes interfere. Replacement remotes and receivers are still available from specialty vendors, but originals—especially with intact rubber keypads—are prized.
Programmable Track Selection
This was the +6's party trick: skipping to specific tracks on stacked records. Using a memory bank, the user could program sequences across multiple albums, say side two of a Beatles record, then a single track from a Stevie Wonder LP, then the rest of a jazz album. The system used optical sensors to detect lead-in grooves and track starts, then counted revolutions to determine position. It wasn't perfect. Deeply modulated grooves or inner-groove distortion could confuse it. No other changer offered this level of control, and even high-end manual turntables couldn't match it without human intervention. The programming interface was simple: a numeric keypad on the remote let you enter track numbers, and the system would execute the sequence automatically.
Gentle Record Handling
BSR's engineering team went after one of the changer's oldest problems, the clattering drop. Instead of letting records fall freely, the +6 used a concentric spindle with a rising platform. As each record finished playing, the entire stack would rise slightly, then the played record would be lowered gently onto the stack below. This minimized impact and reduced the risk of damage, which matters when stacking six LPs. The mechanism was complex, with multiple solenoids and limit switches. When maintained, it ran with a deliberate rhythm. Service technicians observe that dried grease is the most common failure point, leading to misalignment or incomplete lowering cycles.
Historical Context
The mid-1970s were a golden age of automation in consumer audio. The idea was to *manage* music, not just play it. The ADC Accutrac 4000, launched in 1976, was one of the first turntables to advertise its computerized logic and remote control as core features. Its tagline was "Its mother was a turntable, its father was a computer." That reflected a moment when home electronics were becoming intelligent, responsive, even playful. The +6 arrived shortly after, adding multi-record capability without giving up the smart features.
It competed in a crowded field. Technics offered high-end direct-drive decks, Sony and Pioneer pushed compact all-in-one systems, and cheaper changers from BSR's own house brands flooded department stores. The +6 stood apart by blending audiophile-grade components (like the LMA1 cartridge) with genuine innovation. It wasn't a purist's table, and it wasn't a disposable appliance. It was a hybrid for the record lover who also wanted convenience. Toshiba had experimented with optical track detection earlier, but ADC brought it to the mainstream with better marketing and more reliable execution.
The +6 also reflected BSR's dual identity. A British company was building for an American brand, so it combined European engineering with U.S. market savvy. The wooden base and clean lines gave it a more serious look than the space-age 4000, for buyers who wanted automation without the gimmickry. It kept the mushroom receiver and the same core logic board.
Collectibility & Value
Today, the ADC Accutrac +6 is a cult favorite, less common than the 4000 but equally loved. Fully functional units in good condition typically sell between $250 and $450, with restored models reaching $600 or more. The original remote and receiver add significant value. Missing or nonfunctional remotes can knock $100 or more off the price. Units with original manuals, especially the service manual, are rarer and command premiums among tinkerers.
Common failures include dried belt syndrome (the rubber belt degrades over time, causing speed instability), worn motor brushes (in the changer mechanism), and failed capacitors in the control board. The infrared receiver's LED often burns out, and the remote's rubber keypad can disintegrate. LP Gear still stocks replacement belts and cartridges, but the original LMA1 stylus is discontinued, though compatible replacements exist. Recapping the power supply is recommended for any unit that's been stored for decades, as leaking capacitors can damage the logic board.
When buying, test the full cycle: stack records, program a sequence, and watch the changer execute. Listen for smooth motor operation, proper tracking, and clean remote response. Check the dust cover hinges—many have cracked—and inspect the platter for warping. A unit that powers on and spins is only the beginning; the real test is whether it can *think* like it used to. And if it does? You’re not just owning a turntable—you’re hosting a little piece of 1970s futurism in your living room.
Similar items on eBay
No exact ADC Accutrac 6 listings are live right now — these searches show current ADC and similar vintage audio gear on eBay:
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.
Service Manuals, Schematics & Catalogs
- Catalog — archive.org
- Catalog (1989) — archive.org
- Catalog — archive.org