A cassette masterpiece remembered for its innovative RS mechanism
METAL ALLOY Reference Standard Mechanism
First generation: 1979
C46: 1,750 yen.
The first generation was released in 1979 as TDK’s first Metal tape. Scotch had introduced the world’s first Metal tape the previous year, and with Japanese Metal tape eagerly awaited, its debut caused a sensation. Its appearance was striking, but so was its price: 1,750 yen for a C-46. The cassette attracted an enormous response, and sales exceeded expectations.
Explanatory notes
When people first saw the original MA-R, they were astonished. The reason was the RS mechanism (Reference Standard Mechanism), a cassette shell design used by TDK for the first time. A die-cast metal frame was sandwiched between transparent plastic plates. Both its construction and its appearance were unlike those of any previous cassette.
The frame was die-cast as a single, highly accurate component using a special precision mold. This ensured precise tape positioning and stable transport, with little change over time. The transparent plates used a material with clarity comparable to plastic lenses, high hardness and heat resistance; the molding process also reduced internal distortion. The shell’s internal sheets were transparent too, leaving the entire mechanism visible and making the tape look like that of an open-reel recorder.
Plastic plugs on the top of the cassette replaced the usual erase-protection tabs. Tabs could not be formed in the die-cast upper section, but the plugs were a convenient new idea: simply changing their orientation enabled recording again.
The tape itself used Finavinx Metal magnetic material (ファイナビンクス). TDK’s proprietary oxidation protection ensured long-term stability, while ultrafine particles reduced noise. Coating employed a new binder system and a new particle-orientation technology.
The MA-R weighed 80 g, roughly twice the 38.5 g of an ordinary cassette. Apparently, this sometimes prevented it from ejecting from certain decks and car stereos even when the eject button was pressed.
The substantial weight and cool metal feel of an MA-R in the hand were distinctive, as was the sight of the tape turning inside the frame. The design expressed the idea behind it: the cassette mechanism is part of the deck.
TDK sales representatives supplied MA-R samples to various audio manufacturers. It is said that this once led to the MA-R appearing on an advertising poster for a new Pioneer deck.
An insider’s recollection
Development of the MA-R began with an instruction to create the very best, regardless of profitability. For sound quality, the concept was to approach the sound of an open-reel recorder. But the idea of using a die-cast frame, which emerged during development, came as a surprise. I think the design department deserves considerable credit. The factory colleagues who understood the designers’ intention and brought it to life also did a fine job. I believe TDK really put everything it had into this cassette.
Hatakeyama (畠山), former TDK employee.
Its defining feature: the die-cast frame
Pick up an MA-R and its weight, 80 g, clearly sets it apart from other cassettes. The secret is the die-cast frame. That weight also helped stabilize tape transport.
Specifications
- Tape type: Type IV.
- Magnetic material: ultrafine alloy powder.
- Maximum remanent flux density: 3,000 gauss.
- Coercivity: 1,050 oersted.
- Squareness ratio: 0.82.
- Operating bias: +3.5 dB relative to the High Position reference tape.
- Sensitivity: -0.5 dB (333 Hz); 0 dB (3 kHz); +0.5 dB (10 kHz); +2.0 dB (16 kHz).
- MOL: +5.0 dB (333 Hz); -4.0 dB (10 kHz).
- Sensitivity variation: 0.3 dB.
- Bias noise: -60.0 dB.
Sensitivity and MOL values are also given relative to the High Position reference tape.
1979 advertisement
The MA-R embodied TDK’s approach to making products: Creation. Advertising from 1979, when the MA-R went on sale, used the slogan TDK Philosophy.
New. Reference Standard Mechanism. MA-R cassette for the Metal position.
C46 (46 minutes): 1,750 yen; C60 (60 minutes): 2,000 yen.
Second generation: 1981
C46: 1,350 yen.
The second generation was released in 1981. A new binder system and other changes improved particle dispersion and orientation. Even denser packing of the metal particles improved performance and produced more detailed sound. The price, meanwhile, was reduced to 1,350 yen for a C46.
Third generation: 1983
C46: 1,350 yen.
The third generation was released in 1983. With music CDs now on sale, it became suitable for digital sources. The Finavinx Metal particles were made still finer, packed more densely and given a higher degree of orientation. Sensitivity increased by 0.5 dB in the low and middle frequencies and by 1-1.5 dB at high frequencies. MOL, the practical maximum recording level, also rose by 1.5 dB across the frequency range.
