Balanced MC input on PhonoII?

[KennyK]

I was reading Hifi World yesterday and was particularly interested by the thought of balanced inputs from the cartridge to the PhonoII. I'd like to mount my Turntable on a wall shelf away from the rest of my system, but I'm not particularly keen on having a long run of unbalanced cable directly from the tonearm.

in practical terms, would connecting one of the green earth wires from the step-up transformer to the ground or drain pin (pin 1) of the XLR socket, with the cartridge connected to 2 & 3 (hot and cold) be enough to implement a balanced input in the phonoII with MC step-ups?

[John Caswell]

Hi KennyK,
Well I cannot see any reason not to try this as essentially the primary of the stepup Tx is "floating" ie not connected to any other points so it will tend to be capacitively balanced about earth, so by all means have a go, no harm will come of it
You will need to bear in mind that the primary wires from the cartridge will both be "live" so will need screening right up to the cartridge pins, which hopefully should be done by the pickup arm and you will need to keep the phase correct ie Pin1 is always screen, Pin2 is +ve signal, and Pin3 is -ve signal.
Let us know how you get on.

Regards

John aka Dr John

[KennyK]

Thanks, John. am going to take the plunge - I've ordered some bits from CPC/Farnell so I'll have a look at this when I get my order. does anyone know what the SME pin convention is for the 240degree 5 pin din as I may as well follow that when making up my connector at the tonearm end...