DIN-RCA interconnect grounding scheme

Any clue about this?

I’ve no idea about grounding but it may be worth pointing out that Naim can supply phono to din leads for £115. 

I am more curious about the ‘semi balanced’ twisted pairs... how are you balancing these? Naim is nearly all unbalanced, ie signal ground is constant with respect to signal live.

Anyway from memory pin 2 on the DIN is combined earth/ground... so if you want to combine a shield with your signal ground, then I would ensure you do at one end only.. prefereably the end that is source grounded or the DIN. If your source ground is the phono end.. then you might need to experiment.. and ground at the DIN end anyway... just ensure the shield is connected to one end only.. especially if the cables for left and right are not closely bundled... if they are separated by much and earthed at both ends you have created an inductive loop... otherwise known as an earth loop, and you will be inducing noise/mains hum albeit possibly at very low levels into your interconnect shield/ground 

If by semi-balanced & judging by your description,   I know it as pseudo balanced.   The screen should be connected to signal negative (-ve on Naim) at the source end & left floating (not connected) at the pre-amp end .  I've made such cables,  mostly RCA-RCA  but I've also made a few variations of DIN-DIN.   

I've only once made a RCA-DIN.   I used two x 2 core screened cables with the two cables "Y" connected inside the DIN plug,  so it was actually a "V".               

Thank you for replying.

"Semi-balanced" is a terrible definition (but the only I know) for an unbalanced, shielded cable having two separate wires for signal and return paths and the shield connected to the ground at the source end.

Having to connect a DAC with RCA outputs to a Naim pre, ideally I should link the ground at the RCA end. Unfortunately, I'm new to the Naim world, and I know nothing about Naim grounding scheme. The risk to involuntarily create a ground loop, as Simon says, is real. 

I should have added that a lot of forum people use RCA to DIN with a non-Naim DAC,  as far as I'm aware they don't have anything like pseudo balance screened cables.   I know some use a cable config made by FlashBack Sales & that is made with a pair of coax's

Naim use a 'clean Earth' and in some kit a 'Star Earth' pattern. Phono plugs connect to the chassis of the equipment it is going into. A DIN Earth is kept off the chassis and is there fore clean and not subject to RF interference etc,

You'll find the phono sockets on audio kit are isolated from the chassis and the grounds are connected to the internal PCB signal ground connection. The chassis should be connected to mains earth for safety and depending on the particular component (i.e. a Naim Source where signal and mains ground are connected) there may be a single internal connection between mains earth and signal ground. 

Mike-B posted:

If by semi-balanced & judging by your description,   I know it as pseudo balanced.   The screen should be connected to signal negative (-ve on Naim) at the source end & left floating (not connected) at the pre-amp end .  I've made such cables,  mostly RCA-RCA  but I've also made a few variations of DIN-DIN.   

I've only once made a RCA-DIN.   I used two x 2 core screened cables with the two cables "Y" connected inside the DIN plug,  so it was actually a "V".               

Thank you for your suggestion Mike, in fact we were writing at the same time. The idea for a simpler "V" version looks promising, I only have to find a DIN connector with the right size to allow both cables at once. 

Chris1977 posted:

Thank you for your suggestion Mike, in fact we were writing at the same time. The idea for a simpler "V" version looks promising, I only have to find a DIN connector with the right size to allow both cables at once. 

I tend to go with Mogami as if they don't have it,  I doubt it exists.  Plus all that I've sed sound petty good.   I have managed to cram in a pair of Mogami 2549's into a PREH DIN, but its 6mm OD did not make for a pretty cable. 

 Have a look at Mogami 2697, screened twin,   its 2.5mm OD,  it has lowish capacitance at  57pF/m between cores,  but a highish 300pF/m core to screen.  I've not used it so have no idea what it sounds like.