Originally Posted by
Barry
Sorry - I confused matters by stating the original SME arm connector had 5 pins.
This is not quite correct, the connector is a 4-way Belling & Lee 'Unitor' connector, as shown in your photograph above.. The four ways are used for the two signal channels and their respective return paths. The arm's earth (i.e. connection to the arm's metal work) is made with a fifth fine-gauge wire (the same gauge as that of the signal leads), which connects between the rearmost of the two screws holding the knife-edge bearing saddle in place and a 'thimble' sleeve extending one of the fixing screws of the Unitor connector.
The mating connector (with the pins), has the four signal connections wired to two coaxial cables, which in turn terminate in RCA phono plugs (or as an option a 5-pin DIN plug). The arm's earth connection is made with a lightly sprung 'claw' that grips the thimble of the socket, and is fitted with two wire leads: one is connected to the metalwork of the preamp (or phonostage), the other is connected to the metalwork of the turntable.
That explains a lot Barry, it turned out the fine earth wire was broken and has now been replaced with much better wire. The whole arm has been rewired with VDH MSS7 and new VDH gold cartridge tags. The bearing is in good order and no other work was needed. I'm really happy with the results and it wasn't too pricey either.
Turntable
Toshiba SR-370/Mission 774/Van Damme cable with MS Starline plugs/Ortofon Quintet Black
CD
Cambridge CXC transport/modified Musical Fidelity X-DAC/modified Musical Fidelity X-10 V3 tube buffer
Network Player
Cambridge NP30
Amplifier
Denon HA-500 head amp/Nakamichi CA-5E pre-amp/Chinese passive RVC/Proton AA-1150 DMC power amp
Speakers
Mordaunt Short Signifer on original factory stands
Cables
Mogami with Rean Neutrik plugs/NVA LS5
Headphones
Sennheiser HD600/Sennheiser HD650/Koss Pro4 AA