BANG OLUFSEN MMC6000 STYLUS CART QUADRAPHONIC NEW SQ4 CD4 BEOGRAM UNIQUE B&O

BANG & OLUFSEN MMC6000 QUADRAPHONIC STYLUS CARTRIDGE NEW SQ4 CD4 BEOGRAM 4000 4004 B&O 
Uniquely, this cartridge was presented to me by a Bang and Olufsen engineer with the newer type stylus guard that is open from the top. This is the same as found on the new 20 series cartridges and so makes this a one-off.
Please see the comparison photograph next to an MMC 4000 cartridge of the same series and also the second photograph of what every other MMC 6000 looks like with regards to the stylist surround.
A true CD4 quadraphonic pick-up cartridge, originally specified for the Beogram 6000 - see explanation belowAlso suitable For Beogram 4000 4002 and 4004 specifically and Tangential tone arms especially but interchangeable with many others Shibata profile Diamond keeps better contact with the groove and provides a better signal to be amplifiedUnused from new apart from testing Buy with confidence - Over 100 MMC Cartridge stylii sold in new or new other condition with 100% feedback (most on my other "channel" Qualitronics)
The QUALITRONICS DIFFERENCE
All cartridges were sourced directly from Offical B&O showrooms and staff. They are new, some with original
packaging but as they ceased manufacture at least 25 years ago they are labelled old stock.
 
Match with:Beogram 3400, the first B&O CD4 Quadraphonic radial deckBeogram 6000, 4004 or 4002 with CD4 circuit (look for a switch on the right hand bezel)Any tangential Beogram that used the 'thousand' or '20' series of cartridge styli. Still and exemplary pickup in stereo only use
Upgrade with:Not an upgrade but the successor cartridge MMC20CL
Most of these are available in my other listings already or I have them in stock so do have a look below, if not I can source them for you in a few days. Please message me for that service.
Manufactured: 1974 - 1979
Designer: Subir Pramanik
Colours: SilverBang & Olufsen's (then) most accomplished pickup cartridge was fitted to Beogram 6000The MMC principle was adapted to track 4-channel records: both Quadradiscs and SQ. MMC 6000 would track both mono and stereo records with the utmost fidelity. It was designed for record-players with tangential arms. The stylus was the Pramanik diamond, named after its inventor: engineer S K Pramanik from Bang & Olufsen's Laboratories.The diamond's radii were 7 um/2 x 50 um. It was a refinement of the elliptical shape, rather like the shape of the cutter-head, and enabled greater contact with the undulations of the record groove. The cantilever was made of berylium - a material which is harder yet lighter than popularly-used aluminium. Effective tip mass was 0.22 mg. Compliance was higher than 30x10-6 cm/dyne. Recommended- stylus pressure was 1g. The total frequency range was 20-45.000 Hz.In the audible range: 20-15.000 Hz there is less than 1.5 dB variation and in the inaudible range 20,000-45,000 Hz where the carrier frequencies lie, the pick-up fulfils RCA/JVC's specifications for a Class A discrete 4-channel pick-up cartridge. Each cartridge is an integrated, individually calibrated unit. The stylus unit is not separately replaceable since it is part of the integrated unit. An individual frequency response curve traced on a Bruel & Kjaer level recorder and a complete Calibration Card were enclosed with every MMC 6000 sold.MMC6000 Product SpecificationsPramanik diamond
Radius of curvature CD-4 quadro
Frequency range 20 - 15000 Hz+/- 1,5dB 20 - 45000 Hz (CD4)
Channel separation 1000Hz >25dB
40 - 10000Hz >20dB
Channel difference <1,5dB
Intermodulation <1%
Recommended stylus pressure 1g
Compliance 30 x 10(-6)cm/dyne
Effective tip mass 0,22mg
Output mV/cm/sec. 0,6mV/47kOhms