Revox by Willi Studer – gần một thế kỷ tự hào
The world turns.
Revox tape machines
A success story.
A small choice of milestones in the history of Revox tape machines
Revox G36, Tape recorder (1963)
The complete reworking of the F36 to create the Revox G36 marked the pinnacle and also the final chapter in the development of reel-to-reel tape decks with tube electronics. The replacement of the “green series” by a modern grey/blue version, was more than just face lifting. The device was made bigger, in order to enable it to take tape reels up to 26.5 cm (10.5″) as well. For the first time, a synchronous motor was used to drive the reels, which guaranteed the absolute speed, within very tight tolerances. Through the use of a solid die-cast bridge, the new capstan motor together with the clamping arm and recording head block formed a very stable unit. Finally, during the lifetime of the G36, a non-contact photoelectric tape end switch was used for the first time. In order to achieve even tape take-up during fast winding, the reel that was unwinding was braked slightly through an inverse voltage on the take up motor. In comparison to the F36, the amplifier electronics remained largely unchanged with one important exception. Modern, illuminated display instruments, so-called volume unit meters were used for showing recording levels, which meant that one tube less was used. When the last Revox G36 came off the production line in Regensdorf in 1967, this signified the end of the most successful product series in the company’s history.
The Revox G36 very rapidly developed into a best-seller both domestically and abroad and just a few months after its market launch, several consumer protection organisations were already taking an interest in it. In 1964, a well-known North American test laboratory carried out comparison tests with other reel-to-reel machines in the same price class. In the resulting comparative report, the Revox G36 was top in price, performance and quality and was judged to be a “best buy”.
Revox A77 (MK I to MK IV), Tape recorder (1967-1977)
The launch of the Revox A77 marked the start of the company’s most successful tape recorder range. The first sales brochure was entitled “Tradition and Progress” and didn’t just present a new tape recorder but a hi-fi line that also included an amplifier and an FM tuner.
The company’s experiences in the construction of tape recorders since 1949 and the development of a completely new approach based on the stable silicon planar technology, enabled the company to break new ground. Pluggable terminal amplifiers made the direct connection of two loudspeakers possible. The German designer Manfred Meinzner was involved in the new development and he ensured that the complete line had a concise appearance.
The A77’s complete drive was mounted on a stable, torsion-free die-cast chassis. To give added stability, the motor mounting, recording head block and even the side walls were also die-cast. The A77 could also be used standing vertically, without any restrictions. Of course, it had a 3-motor drive. The really special feature was the capstan motor. The robust asynchronous motor was true pioneering work. As a worldwide innovation it was not just smaller, lighter and much less heavy on energy consumption. Its speed consistency was also independent of fluctuations in mains power frequency and voltage levels. The secret was an electronic speed controller that could handle both 50 Hz and 60 Hz (USA) operation without any adjustment.
For the first time, a tape recorder aimed at the amateur market had professional, all metal recording heads. The complete “solid state” electronics were mounted on pluggable printed circuit boards making service very easy. Drive control was done through free-moving pulse push buttons and the relay control not only enabled the remote control of all functions but it also meant that it was protected electrically against incorrect operations.
The A77 featured calibrated VU meters, a photoelectric tape end switch, a four-position tape counter and a controllable, stereo headphone output. It also included take-up motors that could be switched off, a special cutter button for tape splicing as well as a wide range of trick options. A comprehensive, illustrated User manual, the “Red booklet” soon became a textbook for budding recording engineers.
Many different versions appeared during the ten years that the Revox A77 was produced. Even the first brochure listed five versions of each of the 2 and 4 track devices. In addition, there were special radio station versions, e.g. the A77-PTI and the A77-ORF. Of particular interest was the version with integrated Dolby™ B System, which delivered an impressive 70 dB signal-to-noise ratio, (19 cm/s, 2 track, ASA-A Standard) with a distortion factor of better than 1% at full power or better than 0.5% at 0 VU power (185 n/Wb/m).
In the January 1969 edition of the North American specialist magazine “Stereo Review”, the authors from the Hirsch-Houck Laboratories call the servo-controlled drive system “unique and effective”, and describe the frequency response as “phenomenal” and come to the telling conclusion: “We have never seen a recorder that could match the performance of the Revox A77 in all respects, and very few that even come close”.
In 1978, the Japanese specialist magazine “Audio Specialist”, awarded the Revox A77 1st prize as the best “non-Japanese reel-to-reel tape machine”.
Revox B77 – máy ghi âm băng cối (1977-1998)
A completely new hi-fi range was showcased at the 1977 audio specialist exhibition, together with the Revox B77 reel-to-reel tape deck. As well as the B750 amplifier and the B760 FM tuner, this included the B790 record player and the BX series speakers.
There weren’t any significant differences between the B77 drive and the tried-and-tested A77 design. Rather , new features had been integrated during the development, which previously had only been available in the exclusive and expensive A700. The B77 was controlled though pinch-point buttons. An integrated drive control logic handled the execution, taking into account the movement state of the tape through tape sensors. In this way, there was remote controllability of all functions. An external capstan motor control permitted tape speed variations of +/- 10%. The B77 was equipped with a cutter and gluing bar to make tape splicing very easy.
As with the A77, the B77 also had a large number of special versions. The 1980 Dealer price list had no less than 61 models and version and in 1988, the Retail sales price list still had 28 different models.
As well as the standard version with speeds of 9.5/19 cm/s, there were also the following models: B77-HS with 19/38 cm/s (High Speed), B77-LS with 4.75/9.5cm/s (Low Speed), B77-SLS with 2.38/4.75 cm/s (Super Low Speed for monitoring tasks), B77-AUTO with automatic start of recording as well as three versions with additional pilot head for slide projector control tasks ranging from the simple to the complex. B77 synchronous tape recorders had a clock track amplifier for professional synchronous recordings from the recording head. Finally, the B77-DOL offered separate Dolby™ B processors for recording and playback, i.e. “dolbyised” read-after-write, for the highest signal-to-noise ratio (19 cm/s, half-track, better than 74 dB).