TEAC Reference 500 (1997) | The H-Series Mini System That Put Separates in a Compact Format

The TEAC Reference 500 was far more than an ordinary mini system—it was TEAC’s attempt to bring genuine separates-class engineering into a compact, modular package. With substantial aluminium front panels, independent power supplies and a surprisingly sophisticated component lineup, the Reference 500 remains an intriguing piece of vintage audio history.

TEAC Reference 500 – Main Specifications

System concept: H-Series modular mini system

Core components: R-H500 cassette deck, PD-H500 CD player, T-H500 stereo tuner and A-H500 stereo amplifier

Optional components: AG-H500 stereo receiver, AV-H500 Pro-Logic Surround Amplifier, VRDS-9 CD player, PD-H503 multi-CD player, RW-H500 CD recorder and MD-H500i MiniDisc recorder, DV-H500 DVD player

Construction: 10 mm thick aluminium front panels

Chassis: High-rigidity construction

Connections: Gold-plated RCA jacks

Remote control: Full-function infrared control system

Amplifier design: Separate left/right circuits

Power supply: Fully shielded toroidal transformer and upgraded 4-ohm power supply

CD input: Direct CD switching for a shortened signal path

Architecture: Modular components with individual power supplies

Expansion: Designed to accommodate future components and upgrades

The H-Series Concept: Miniature Separates, Not a Typical Mini System

The H-Series philosophy was simple: reduce the physical size without reducing the quality of the individual components. Rather than building everything into one chassis, TEAC divided the system into separate amplifier, CD player, tuner and cassette deck units. Each component had its own enclosure and power supply, making the Reference 500 much closer in spirit to a traditional separates system than a conventional all-in-one mini system. The construction was equally serious. Every component used a substantial 10 mm aluminium front panel, giving the system a distinctive, high-end appearance while contributing to rigidity and durability. The high-rigidity chassis construction was another indication that TEAC was targeting enthusiasts rather than casual mini-system buyers. A System Designed to Grow. Modularity was one of the Reference 500’s strongest features. Owners could start with the basic four-component system and expand it as new technologies became available. The Reference 500 family eventually included considerably more than the original amplifier, tuner, CD player and cassette deck. Additional components included a Pro-Logic surround amplifier, multi-CD player, CD recorder, MiniDisc recorder and other system components. The A-H500 Amplifier: Simplicity With Serious Engineering. At the heart of the system was the A-H500 stereo amplifier. Its design incorporated separate left and right circuits, a fully shielded toroidal transformer and an improved power supply intended to handle 4-ohm speaker loads. TEAC also kept the signal path deliberately straightforward. The CD Direct function was particularly interesting. When selected, the CD signal could bypass unnecessary circuitry, providing a shorter and cleaner path between the source and amplification stage. For vintage audio enthusiasts, this is an important detail because it reflects an engineering philosophy that was common in serious hi-fi equipment: eliminate unnecessary processing rather than simply adding features. Intelligent System Control. The Reference 500 also attempted something surprisingly advanced for its era: system-level automation. The components were designed to communicate intelligently through the control system. For example, pressing PLAY on the CD player while listening to FM could automatically switch the amplifier to the CD input and begin playback. Similar interactions were available between the tuner and cassette deck. The system could even automatically activate previously configured RDS functions when traffic information was received. Today, this behaviour seems ordinary. In the context of a vintage component system, however, it was an impressive attempt to make separate hi-fi components operate as a unified system. 

The Hidden Story: Who Actually Built the Reference 500?

Here is where the Reference 500 story gets particularly interesting. Although these components carried the TEAC name, the H-Series units were actually manufactured in Korea by ANAM. ANAM was an important OEM manufacturer and produced equipment not only for its own brand (including the above shown Teac components) but also for other companies. The same or closely related hardware can therefore be found under different brand names, including Akai and Universum, the latter being associated with Quelle in Germany.

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PIONEER SX-3500 (1980) | 20 Watts of Classic Pioneer Engineering

The Pioneer SX-3500 from 1980 was a compact vintage stereo receiver that combines a 20-watt-per-channel power amplifier with a highly sensitive FM/AM tuner and a carefully engineered phono section. Introduced as a practical alternative to oversized, high-power receivers, the SX-3500 focuses on clean performance, useful headroom, and sophisticated circuitry without unnecessary complexity.

Pioneer SX-3500 Main Specifications

Continuous power output: 20 watts per channel, both channels driven

Load impedance: 8 ohms

Frequency response: 20Hz–20kHz

Total harmonic distortion: No more than 0.05%

Dimensions: 17 11/16 × 5 5/8 × 12 7/16 inches

Weight: 16 lb 12 oz

Original sale price: 225 USD

The specifications tell only part of the story. The SX-3500's real appeal lies in how Pioneer combined several advanced circuit concepts into a relatively modestly powered receiver. Pioneer SX-3500 Circuit Design and Proprietary Technology. Bootstrapped Power Amplifier. Pioneer used a time-tested amplifier topology rather than chasing extremely high output figures. The SX-3500's power amplifier employs a current-mirror-loaded differential input, followed by a bootstrapped predriver and a fully complementary push-pull output stage. Each channel uses two specially selected power transistors in the output stage. With 20 watts per channel available continuously into 8 ohms and distortion limited to 0.05%, Pioneer considered this enough power for a typical listening room while retaining useful reserve for musical peaks. The brochure makes an important point about amplifier power: average musical levels require surprisingly little power, while short-lived peaks can demand considerably more. The SX-3500 was designed around this principle rather than simply competing on headline wattage. FLUROSCAN™ Power Meters. The blue FLUROSCAN™ bar-graph meters provide a visual indication of moment-to-moment amplifier output. Sensitive FM Front End. Pioneer's FM tuner begins with a carefully designed front end using a junction-type FET RF amplifier, transistor mixer and three-gang variable capacitor. The result is an FM usable sensitivity of 11.2dBf (2.0µV) in mono, a respectable figure for a receiver designed for the mainstream hi-fi market. Pioneer IC IF Section. The intermediate-frequency section uses a Pioneer-exclusive IC together with two two-element ceramic filters. The filters help reject noise, distortion and interference, while the transistor IF amplifier provides additional signal gain before the FM signal reaches the stereo demodulator. PLL Stereo Multiplex. A PLL multiplex circuit provides stable stereo decoding while helping maintain wide channel separation and low distortion. Pioneer also used an active low-pass filter to remove the pilot-signal components after they had served their purpose in separating the left and right channels. Low-Noise Phono Equalizer. The phono stage was given serious attention, rather than being treated as an afterthought. Pioneer's discrete two-transistor phono equalizer provides a specified 76dB signal-to-noise ratio. RIAA equalization is specified within ±0.3dB over 30Hz–15kHz, making the phono section an important part of the SX-3500's overall design. Power NFB Tone Control. Bass and treble control are integrated into the power amplifier's negative-feedback loop. Pioneer called this arrangement the Power NFB circuit. Rather than relying on a more elaborate separate tone-control architecture, the design was intended to provide an acoustically flat response while allowing bass and treble emphasis or attenuation when required by the listening environment.

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TEAC AL-700 (1976) | Esoteric Series

The TEAC AL-700 Elcaset Deck was introduced in 1976 as TEAC's first—and only—Elcaset deck. Developed around the ambitious "Open reel sound on cassette" concept, it combined 6.3 mm-wide tape, high tape speed, and sophisticated open-reel-derived mechanics in a cassette format.

TEAC AL-700 Specifications

Model: TEAC AL-700 Elcaset Deck

Release: 1976

Track format: 4-track, 2-channel stereo

Head configuration: 3-head — erase, record, playback

Tape: Elcaset LC-60 / LC-90, Type I, Type II, Type III

Tape speed: 9.5 cm/s

Capstan motor: FG servo DC motor

Reel motors: Coreless DC motors ×2

Wow & flutter: 0.04% WRMS

Frequency response: 25 Hz–20 kHz ±3 dB, Type I; 25 Hz–22 kHz ±3 dB, Type II/III

Signal-to-noise ratio: 59 dB Type I; 62 dB Type II/III

Total distortion: 0.8% Type II

Fast rewind: Within 70 seconds with LC-60 tape

Inputs: Microphone and line, with independent level controls

Outputs: Line and headphone

Noise reduction: Dolby B, with external dbx capability

Power consumption: 37 W

Dimensions: 440 × 230 × 310 mm

Weight: 18 kg

Original sale price in Germany: 2.900 DM (dbx unit: 1.200 DM)

The Elcaset Concept

Elcaset was designed to bring open-reel performance to a cassette. The format was jointly developed by Sony, TEAC, and Technics and used 6.3 mm-wide tape—the same width used by open-reel machines—inside a much larger A-6-sized cassette. With a tape speed of 9.5 cm/s, the format offered considerably more tape area for recording than a conventional cassette. The result was an ambitious attempt to combine the convenience of a cassette with the sound quality associated with open-reel tape. A major difference was the outer tape guidance system. Instead of relying entirely on the precision of the cassette shell, the AL-700 pulled the tape out of the cassette and controlled it with the deck's own transport mechanism. This approach allowed TEAC to use sophisticated mechanisms such as a dual-capstan transport and three-head arrangement. TEAC's Open-Reel Technology in an Elcaset. Its three-motor drive system used an FG servo DC motor for the capstan and two coreless DC reel motors, directly reflecting TEAC's experience with three-motor open-reel machines. Twin-Belt Closed-Loop Dual Capstan. The twin-belt system was one of the AL-700's most distinctive mechanical features. Its closed-loop dual-capstan transport used two sets of capstans and pinch rollers to grip the tape and maintain controlled tension. The slight difference in capstan speed helped suppress tape movement and flutter caused by external disturbances. However, excessive speed differences could produce excessive tension, which was particularly undesirable with relatively thin Elcaset tape. TEAC therefore added a wide auxiliary belt directly to the outer flywheel. This belt acted almost like a mechanical servo, helping maintain soft and consistent tape tension while also reducing stress on the main drive belt and flywheel. High-Precision Fixed Head. TEAC also paid unusual attention to head mounting accuracy. The AL-700 used a fixed-head system derived from TEAC's in-vehicle data recorder technology. A precision die-cast structure and central locating pin determined the head's height, tangency, and tilt. Azimuth could then be adjusted with a single screw, allowing the head to pivot around the central reference point without changing its height. The result was a considerably more precise head-mounting system than the conventional three-point adjustment arrangement. Automatic Self-Aligning Pinch Roller. The pinch roller was another example of TEAC's data-recorder engineering. Several metal balls surrounding the roller shaft allowed considerably more movement than a conventional pinch roller. This gave the roller the ability to compensate for a tilted shaft or uneven rubber wear while maintaining even pressure against the capstan. Magnefloat Capstan. TEAC's Magnefloat system addressed unwanted capstan shaft movement. Magnets positioned near the flywheel and bearing used magnetic repulsion to keep the capstan shaft pressed against a defined point. Unlike a spring-loaded mechanical arrangement, the system produced very little mechanical noise and friction. It also avoided changes in clamping force caused by temperature variations and was designed for long-term durability. Three-Head Recording and Dolby Noise Reduction. The AL-700 used a true three-head configuration, with separate erase, record, and playback heads. The record and playback heads were made from high-hardness permalloy, while the erase head used ferrite. The deck supported Type I, Type II, and Type III Elcaset tapes, with automatic bias and equalization selection through detection holes in the cassette shell. Dolby noise reduction could also be selected automatically through the cassette's detection tab. The deck additionally incorporated an MPX filter to prevent problems caused by the 19 kHz FM stereo pilot signal during radio recording. For users wanting even greater noise reduction, TEAC provided a dedicated connection for the separately sold dbx RX-10 unit. Recording and Control Features. The AL-700 was far more sophisticated than a simple playback deck. Its microphone and line inputs had independent level controls, allowing microphone mixing during recording. A centrally positioned REC MUTE button made it possible to create silent sections while recording, while the large VU meters displayed average input level and independent peak indicators helped monitor momentary overloads. The transport was operated through soft-touch microswitches and logic circuitry. Additional functions included timer operation, memory auto-stop/auto-play, output volume control, mono/stereo switching linked to the microphone input, and a Dolby copy function. The Elcaset format itself provided automatic detection for tape type and Dolby selection, allowing the AL-700 to configure important recording and playback parameters without manual intervention.

External Accessories

The AL-700 could be expanded with dedicated accessories. TEAC offered the RX-10 dbx unit and RC-90 remote control as separately sold options. TEAC RX-10 dbx unit: ¥78,000 | TEAC RC-90 remote control: ¥10,500

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