This tangential-tracking record deck offered superb sound quality from records plus the assurance that its playing precision minimised groove wear and kept your albums ‘like new’ for a very long time.
Operation was totally automatic. Record size and speed were identified by a ‘magic eye’ (photodiode) carried on a detector arm which travelled ahead of the tone arm. Fast and slow scan (both inward and outward) facilities allowed you to locate and play inner tracks without touching the delicate arm or pick-up.
The pick-up was the MMC3 with an unframed elliptical diamond carried on a tapered tubular cantilever of aluminium. The total effective tip mass of this arm/pick-up combination was a mere 0,35mg – no wonder Beogram 6002 was so kind to your records!
The motor was a DC tacho-motor controlled by an electronic servo-circuit. Turntable drive was via flat belt. The turntable and its bearings were mounted on the same inner chassis as the tone arm, and this was totally isolated from the motor, deck plate and outer chassis by a sophisticated pendulum suspension system.
When connected to Beomaster 6000, Beogram 6002 had a one-way data-link which makes it controllable via the Beomaster’s main controls or optional remote Terminal. Beogram 6002 could be used as part of a full stereo system – the Beosystem 6000 or 8000.
This deck was the Beogram designed for use with the Beomaster 6000.
To all intents the same deck as the Beogram 8000, it had a MMC20EN cartridge and black keys to differentiate it from its more expensive brother. Not replaced directly when the newer cartridges were released as the Beogram 6002 was belt drive rather than tangential drive.
This was a confusing product as it offered the same performance as the Beogram 8000 but was cheaper due to the lesser cartridge. It was not a big seller and it was not surprising that the range was rationalised by keeping a top performing Beogram in the Beogram 8002 and a substantially simpler deck in the Beogram 6002.
Beogram 8002 was a ‘state-of-the-art- product with a performance capability as near ideal as anyone had up till then devised. The platter was driven not by a conventional motor, but by a unique tangential-drive system that had no moving parts and no physical contact with the turntable.
Tangential drive works on the same principle as the ordinary domestic electricity meter (a form of electric ‘motor’ which you have probably always lived with yet been totally unaware of, since its disc continues rotating, silently and accurately, year after year without any maintenance whatever). It is based upon a law of physics by which any current-carrying body placed within a magnetic field experiences a force which will cause it to move.
Bang & Olufsen took full advantage of this simple law by placing the edge of the Beogram’s under-platter between two fixed coils. When current was applied to these coils a magnetic field was created in the gap between them, thus moving the under-platter without physical contact of any sort. The speed of rotation was dependant on the amount of current passing through the coils and B&O’s use of a quartz-controlled electronic servo-circuit to govern current flow keeping the turntable speed constant and highly accurate.
The tangential-tracking arm was made of hard-drawn brass. It carried the pickup in a straight line from the edge of the record to its centre – the same geometry used in cutting the original master-disc – so skating effect did not occur and vertical tracking error was barely measurable. The tone arm was preceded by a detector arm carrying a photodiode which could ‘see’ the surface below it. If the PLAY button was pressed when there was no record on the turntable, this magic eye ‘saw’ the broken pattern of the platter’s black ribs rotating and a safety circuit blocked any user command to lower the pickup. So Beogram 8002 was safe as well as extremely sophisticated.
The pickup arm used the latest type of cartridge – MMC2 – weighing a mere 1,6 grams. Its unframed diamond stylus had a multi-faceted (contact line) profile which could follow every last detail of the groove modulations.
Beogram 8002 had a computerised control system that made operation so easy that you didn’t even have to think about it. Just press PLAY. Machine intelligence identified the size and playing speed of the record. If you wanted to hear the same disc more than once, it was necessary to just press PLAY for each time you want to listen – up to 9 times. The number of repeats you ordered would appear as the last digit on the speed read-out panel.
You could scan the arm – inwards or outwards – to any track on the record in fast or slow motion. Manual override buttons were provided for playing non-standard discs and the pause control made it easy to resume play after an interruption.
Beogram 8002 could be used as part of the Beosystem 6000 or Beosystem 8000
Beogram 3400 was designed to play back quadraphonic-encoded records and incorporated an MMC 5000 with a Shibita diamond stylus. An optional CD4 decoder could be specified to allow play back of that type of LP as well SQ discs which could be played by any record player.
Quadraphonic sound
Bang & Olufsen produced two quadraphonic systems in the 1970s. The top model was Beosystem 6000 which comprised Beomaster 6000 and Beogram 6000. Beogram 6000 was a development of Beogram 4000 in that it was a tangential tracking turntable. It had an inbuilt CD4 decoder which was switchable. When ‘on’ it would detect the presence of the carrier frequencies and a display would illuminate on the record deck’s display as ‘4ch’.
The output of the Beogram was at line-level whether in 2- or 4-channel mode. The deck was attached to Beomaster 6000 via a 5-pin DIN lead with all the pins being wired. In Beomaster 6000 there was a replaceable board with a SQ decoder as standard. This was manually switchable. The operator therefore still needed to know the type of quad recording that was to be played. The purpose of the removable board was to allow upgrading should the record industry ever get its act together and find a common standard!
The second system was based on Beomaster 3400 and Beogram 3400 which had a radial deck and a smaller and simpler receiver. This again had similar functions. Beomaster 4000 and a few others had a facility called Ambiophonics which used a system of simulated four track sound from stereo records. Two Bang & Olufsen cartridges were made for playing CD4 records:
MMC5000 used a fairly standard Shibata profile
The top of the range MMC6000 used a profile designed by one of their own engineers – Subir Pramanik – and which bore his name
Beogram 2200/2400 were identical except that, when coupled to the Beomaster 2400, Beogram 2400 could also be operated by remote control.
To play records on either model it was necessary to simply press START and let the automatic system do the rest. As an additional safeguard, all functions could be operated with the protective lid closed. The electronic servo drive system kept turntable speed constant and correct, even during fluctuations in the mains supply. Careful arm geometry ensured that tracking angle was kept well below the level where it could affect the quality of the reproduced sound.
Bias effect was compensated automatically and needed no adjustment. The extreme lightness of the arm, together with the highly polished nude elliptical diamond carried by the MMC 20EN pickup in the 2400, resulted in an unusually low Effective Tip Mass (ETM). This means that your records would suffer very little wear, even after continual playing. Neither would they be damaged if the stylus was accidentally skidded across the surface.
Beogram 2400 could be made up as part of the Beosystem 2400 when linked together with other compatible Bang & Olufsen products.
Beogram 2200/2400 were identical except that, when coupled to the Beomaster 2400, Beogram 2400 could also be operated by remote control.
To play records on either model it was necessary to simply press START and let the automatic system do the rest. As an additional safeguard, all functions could be operated with the protective lid closed. The electronic servo drive system kept turntable speed constant and correct, even during fluctuations in the mains supply. Careful arm geometry ensured that tracking angle was kept well below the level where it could affect the quality of the reproduced sound.
Bias effect was compensated automatically and needed no adjustment. The extreme lightness of the arm, together with the highly polished elliptical diamond carried by the MMC 20E pickup in the 2200, resulted in an unusually low Effective Tip Mass (ETM). This means that your records would suffer very little wear, even after continual playing. Neither would they be damaged if the stylus was accidentally skidded across the surface.
Beogram 2200/2400 could be made up as part of the Beosystem 2200 when linked together with other compatible Bang & Olufsen products.
Beogram 2202 and Beogram 2402 replaced models 2200 and 2400 and were eventually replaced by Beogram 2404 (looking the same externally as the former units) in 1983.
To play records on the fully-automatic Beogram 2202/2402 decks, it was necessary to simply press “start” and let the integrated systems do the rest. As an additional safeguard, all functions could be operated with the protective dust lid closed.
Thanks to the fine polish of their elliptical diamonds, and the low mass of the arm, these Beograms got the very best from your records without inflicting any significant wear. Careful arm geometry ensured that tracking error was kept well below the level where it could affect sound quality. Skating effect was compensated automatically. Beogram 2202 was fitted with an MMC 20E pickup, while Beogram 2402 has an MMC 20EN. When coupled to the Beomaster 2400-2 FM stereo receiver, Beogram 2402 could be operated by remote control.
Beogram 2202 / 2402 could be made up as part of the Beosystem 1900 or Beosystem 2400, when linked together with other compatible Bang & Olufsen products.
Beogram 2202 and Beogram 2402 replaced models 2200 and 2400 and were eventually replaced by Beogram 2404 (looking the same externally as the former units) in 1983.
To play records on the fully-automatic Beogram 2202/2402 decks, it was necessary to simply press “start” and let the integrated systems do the rest. As an additional safeguard, all functions could be operated with the protective dust lid closed.
Thanks to the fine polish of their elliptical diamonds, and the low mass of the arm, these Beograms got the very best from your records without inflicting any significant wear. Careful arm geometry ensured that tracking error was kept well below the level where it could affect sound quality. Skating effect was compensated automatically. Beogram 2202 was fitted with an MMC 20E pickup, while Beogram 2402 has an MMC 20EN. When coupled to the Beomaster 2400-2 FM stereo receiver, Beogram 2402 could be operated by remote control.
Beogram 2202 / 2402 could be made up as part of the Beosystem 1900 or Beosystem 2400, when linked together with other compatible Bang & Olufsen products.
An updated 2402 but with the revised lightweight arm designed to take the MMC5 cartridge.
Rather an afterthought, the 2404 was designed to work with the Beomaster 2400-2 and was fitted with the 7 pin DIN plug to allow control by remote. This was not compatible with Datalink. The last UK model of this design and interesting simply because it had the new cartridge but the old remote control software unlike the Beogram 6000 which boasted the new software and old cartridge.
