Keeping things turning. Revox tape recorders A success story.
G36 reel-to-reel tape recorder (1963)
The complete revision of the F36 to give the Revox G36 led to the culmination and final stage in the development of tape recorders with valve electronics. The replacement of the «green series» with a more modern «grey/blue» was more than just a facelift. The device was enlarged so that it could also be used with tape reels measuring up to 26.5 cm (10.5″). For tape reel operation, a synchronous motor was used for the very first time, which guaranteed an absolute speed within very tight tolerances. With a solid integral casting, the new capstan motor, together with the pinch arm and recording head, formed a unit with particularly long-term stability. In the tape drive, a contactless photoelectric tape end switch was ultimately implemented over the course of the G36 series. To achieve even tape reeling during quick rewinds, the unwinding spool was braked slightly with a counter-tension on the winding motor. The amplifier electronics remained almost unchanged as compared to the Model F36, but with one important exception: modern illuminated indicator instruments were used as peak programme meters, called VU meters (volume units), which also allowed one valve to be eliminated. When the last Revox G36 left the production line in Regensdorf, Switzerland in 1967, one of the most successful product series in the history of the company came to an end.
The Revox G36 quickly developed into a bestseller both domestically and overseas, and just a few months after being introduced on the market, the device received scrutiny from various consumer protection organisations. A prominent North American testing laboratory performed comparison tests with other tape recorder devices in the same price class in 1964. In the concluding comparison which took into account price, performance, and quality, the Revox G36 ultimately came in first place, and was judged to be the «best buy».
REVOX A77 (MK I TO MK LV), TAPE RECORDER (1967-1977)
The introduction of the Revox A77 kicked off the most successful tape recorder series in the history of the company. The first sales brochure was entitled «Tradition and Progress» and not only presented a new tape recorder, but a new hi-fi line, which also included an amplifier and an FM tuner.
Its experience in the manufacturing of tape recorders since 1949 and the development of an entirely new technology based on the robust silicon planar technology made it possible to forge entirely new paths. Plug-in final amplifiers made it possible to directly connect two speakers. This new product development was assisted by the German designer Manfred Meinzner, who was responsible for the entire line’s striking appearance.
The entire tape drive of the A77 was built on a robust, twist-free die cast chassis. For additional stability, the capstan motor bearings, recording head, and even the side walls were die-cast. The A77 could also be operated vertically without any restrictions. Naturally, it was equipped with a 3-motor tape transport system. But the absolute novelty was the capstan motor. The robust asynchronous motor was a true pioneering achievement. As the first of its kind worldwide, it was not just smaller, lighter, and consumed significantly less energy, but its speed consistency was also independent of the mains frequency and voltage fluctuations. Its secret was an electronic speed regulation mechanism which allowed for 50 Hz and 60 Hz operation (USA) without any modifications.
For the first time, an amateur tape recorder offered all-metal recording heads in a professional version. The entire solid state electronics were built on plug-in printed circuit boards, making them extremely service-friendly. The tape drive was controlled via smooth pulse push buttons, and the relay controls allowed not only all functions to be controlled remotely, but also locked them electrically to prevent operating errors.
The A77 featured calibrated VU meters, a photoelectric tape end switch, a four-digit tape counter, and an adjustable output for stereo headphones. Disengageable reel motors and a special cutter button for tape editing as well as a wide range of trick options were also part of the package. A comprehensive illustrated operating manual, the «Red Booklet», soon became the textbook for aspiring tape enthusiasts.
In the ten years during which the Revox A77 was built, numerous variants were released. The first brochure already listed five variants each for 2- and 4-track devices. There were also special variants for radio, e.g. the A77-PTI and A77-0RF. Deserving of particular mention is the variant with integrated DolbyTM B system, which featured a legendary 70 dB signal-to-noise ratio (19 cm/s, 2-track, weighted as per ASA-A), with a harmonic distortion of better than 1% at maximum level or better than 0.5% at a level of 0 VU (185 nWb/m).
In the January 1969 issue of the North American journal «Stereo Review», the authors of the Hirsch-Houck Laboratories called the servo-controlled drive system «unique and effective», described the frequency response as «phenomenal», and reached the following telling conclusion: «We have never had a tape recorder that measured up to the Revox A77 in every regard, and very few that even came close to it».
In 1978, the Japanese journal «Audio Specialist» awarded the Revox A77 the 1st prize for «best reel-to-reel tape recorder of non-Japanese origin».
REVOX B77, TAPE RECORDER (1977-1998)
The complete revision of the F36 to give the Revox G36 led to the culmination and final stage in the development of tape recorders with valve electronics. The replacement of the «green series» with a more modern «grey/blue» was more than just a facelift. The device was enlarged so that it could also be used with tape reels measuring up to 26.5 cm (10.5″). For tape reel operation, a synchronous motor was used for the very first time, which guaranteed an absolute speed within very tight tolerances. With a solid integral casting, the new capstan motor, together with the pinch arm and recording head, formed a unit with particularly long-term stability. In the tape drive, a contactless photoelectric tape end switch was ultimately implemented over the course of the G36 series. To achieve even tape reeling during quick rewinds, the unwinding spool was braked slightly with a counter-tension on the winding motor. The amplifier electronics remained almost unchanged as compared to the Model F36, but with one important exception: modern illuminated indicator instruments were used as peak programme meters, called VU meters (volume units), which also allowed one valve to be eliminated. When the last Revox G36 left the production line in Regensdorf, Switzerland in 1967, one of the most successful product series in the history of the company came to an end.
The Revox G36 quickly developed into a bestseller both domestically and overseas, and just a few months after being introduced on the market, the device received scrutiny from various consumer protection organisations. A prominent North American testing laboratory performed comparison tests with other tape recorder devices in the same price class in 1964. In the concluding comparison which took into account price, performance, and quality, the Revox G36 ultimately came in first place, and was judged to be the «best buy».
A series with A76, A77 and A78
A series with A76, A77 and A78
Revox A77 (MK I to MK lV), tape recorder (1967-1977)
The introduction of the Revox A77 kicked off the most successful tape recorder series in the history of the company. The first sales brochure was entitled «Tradition and Progress» and not only presented a new tape recorder, but a new hi-fi line, which also included an amplifier and an FM tuner.
Its experience in the manufacturing of tape recorders since 1949 and the development of an entirely new technology based on the robust silicon planar technology made it possible to forge entirely new paths. Plug-in final amplifiers made it possible to directly connect two speakers. This new product development was assisted by the German designer Manfred Meinzner, who was responsible for the entire line’s striking appearance.
The entire tape drive of the A77 was built on a robust, twist-free die cast chassis. For additional stability, the capstan motor bearings, recording head, and even the side walls were die-cast. The A77 could also be operated vertically without any restrictions. Naturally, it was equipped with a 3-motor tape transport system. But the absolute novelty was the capstan motor. The robust asynchronous motor was a true pioneering achievement. As the first of its kind worldwide, it was not just smaller, lighter, and consumed significantly less energy, but its speed consistency was also independent of the mains frequency and voltage fluctuations. Its secret was an electronic speed regulation mechanism which allowed for 50 Hz and 60 Hz operation (USA) without any modifications.
For the first time, an amateur tape recorder offered all-metal recording heads in a professional version. The entire solid state electronics were built on plug-in printed circuit boards, making them extremely service-friendly. The tape drive was controlled via smooth pulse push buttons, and the relay controls allowed not only all functions to be controlled remotely, but also locked them electrically to prevent operating errors.
The A77 featured calibrated VU meters, a photoelectric tape end switch, a four-digit tape counter, and an adjustable output for stereo headphones. Disengageable reel motors and a special cutter button for tape editing as well as a wide range of trick options were also part of the package. A comprehensive illustrated operating manual, the «Red Booklet», soon became the textbook for aspiring tape enthusiasts.
In the ten years during which the Revox A77 was built, numerous variants were released. The first brochure already listed five variants each for 2- and 4-track devices. There were also special variants for radio, e.g. the A77-PTI and A77-0RF. Deserving of particular mention is the variant with integrated DolbyTM B system, which featured a legendary 70 dB signal-to-noise ratio (19 cm/s, 2-track, weighted as per ASA-A), with a harmonic distortion of better than 1% at maximum level or better than 0.5% at a level of 0 VU (185 nWb/m).
In the January 1969 issue of the North American journal «Stereo Review», the authors of the Hirsch-Houck Laboratories called the servo-controlled drive system «unique and effective», described the frequency response as «phenomenal», and reached the following telling conclusion: «We have never had a tape recorder that measured up to the Revox A77 in every regard, and very few that even came close to it».
In 1978, the Japanese journal «Audio Specialist» awarded the Revox A77 the 1st prize for «best reel-to-reel tape recorder of non-Japanese origin».
B77 tape recorder
B77 tape recorder
Revox B77, tape recorder (1977-1998)
Together with the Revox B77 tape recorder, a completely new hi-fi line was presented at the audio trade fairs of 1977. In addition to the B750 amplifier and the B760 FM tuner, this also included the B790 record player and the BX series speakers in a new design.
The tape drive of the B77 tape player did not differ significantly from the tried-and-tested design of the A77. Instead, new features were integrated during the upgrading process which were previously reserved for the exclusive and costly A700. The B77 could be controlled via tactile switches; an integrated tape drive logic controller took care of the execution and also took into account the movement status of the tape via a tape sensor. This allowed all functions to be controlled remotely, and an external capstan motor controller allowed the tape speeds to be varied by +/- 10%. With the cutter switch and an integrated adhesive rail, the B77 was optimally equipped for tape editing.
Like the A77, the B77 was a tape recorder with a large number of special variants. The 1980 distributor price list contained no less than 61 models and variants, and the 1988 sales price list still listed 28 different models.
Apart from the standard version with the speeds 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-AUT0 with automatic recording start as well as three variants with additional pilot head for simple to sophisticated slide projector control systems. B77-Synch tape recorders were equipped with a timing track amplifier for professional dubbing recordings from the recording head. Finally, the B77-DOL offered separate DolbyTM-B processors for recording and playback (i.e. «Dolbyised tape monitoring) for a maximum signal-to-noise ratio (19 cm/s, half track, better than 74 dB).