MMC1

Manufactured: 1984 - 1996
Designer: Jacob Jensen
Colours: Silver and Black

The MMC1 was the top of the range of B&O's new cartridge range.

It was only available as an upgrade - even the top of the range Beogram 8002 was only fitted with the MMC2 The MMC1 had a line contact diamond mounted on a tubular sapphire cantilever.

The tubular construction offered less weight than a solid cantilever but with immense stiffness. The diamond profile was similar to that of the MMC20CL being line contact. The way to look at these cartridges was to imagine an elliptical profile but with both the front and rear facets being scooped out. In this way the vertical contact surface was maximised and the horizontal element kept to a minimum.

The MMC1 and MMC2 were essentially the same cartridge with the MMC1 using the best specified diamond tips. The MMC system was carried over from the SP series but taken to an even smaller level.

MMC stands for 'Moving Micro-Cross'; the patented moving-iron principle upon which all B&O cartridges were based. This unique system employed a cross-shaped armature which, among other advantages, guaranteed exceptional stereo separation since each channel moves on a separate axis.

The job of any pickup cartridge is to transform the record's physical profile (groove modulation) into corresponding electrical signals (which are then amplified or enlarged by the amplifier and turned into audible sound waves by the loudspeaker.

A cartridge must perform three separate and exacting tasks if it is to do this job successfully. It must function mechanically (the movements of the stylus in the groove); it must function magnetically (using the physical movements to create changes in a magnetic field); and it must function electrically (using the changes in magnetic flux to generate an electrical current). At each stage, one type of energy is transferred into another, quite different, type. And the transfer must be perfect, with no energy lost and none added from extraneous sources.

No cartridge will ever reach this ideal unless the Laws of Physics can be repealed. However, by understanding the relationships between the three transfer stages and continually applying refined engineering techniques, B&O's belief was that each stage of cartridge improvement would bring each successive cartridge closer to the ideal.

Record wear and the cartridge

If you take music seriously the value of your record collection is likely to be high. Many of your records are likely to be irreplaceable. You will also know that the signals pressed into your vinyl discs are very fragile indeed. The pickup cartridge can be the disc's worse enemy since an ill-suited cartridge can mark a record for life in a single play.

While B&O is aware that cartridge specifications are inter-related, their research shows consistently that Effective Tip Mass (ETM) is one of the major factors affecting record wear. ETM is the equivalent of the amount of inertia the groove 'sees' in moving or accelerating the stylus tip. Consequently, the higher the ETM value, the higher the force required for a given constant acceleration. Obviously, more force results in more wear.

Three elements contribute to ETM. The stylus tip (diamond) contributes with its entire weight and mass. The armature contributes between 5 - 20% of its weight and mass; the cantilever around 30%. B&O has been able to reduce ETM substantially by refining these elements and building them into an integrated unit. The result is a system which not only reduces damage to the groove walls dramatically, but also provides exceptional performance at all frequencies.

MMC1 Product Specifications

DescriptionNude multi-radial Contact Line diamond, mounted on a sapphire cantilever
Tracking force - grams1
Diamond Stylus Cont. line nude
Cantilever tubeSapphireEffective tip mass mg0,25
Compliance mg/mN 30
Frequency 20-20000 Hz=/-dB1
Channel separation 1000>dB30
Output mV/cm/s RMS0,6
Cartridge weight gram1,6