Balanced tonearm cable

Atmasphere said:

OK. From the diagram and photos above, the tonearm cable seems OK. I'm thinking the problem is the phono preamp.

If the phono preamp is really balanced and if it also has RCA inputs that work, and also if the balanced input is properly designed, then if one wire were disconnected from either pin 2 or 3 of the XLR, in balanced mode the phono section would not play on that channel. So I think this is worth checking.

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I bought the unbalanced cable ( https://www.audiophonics.fr/fr/cabl...-femelle-5-broches-2-rca-noir-15m-p-4721.html) because the unbalanced connection is working on my turntable and the preamp.

I still have the "bad/defective" balanced cable that I am planning to fix. I have no idea when I will fix it. I also have to solder 4 Grado headphones. The Grado job has priority.

I am pretty impressed by the unbalanced phono cable! It seems to be worth to invest a bit money into a new phono cable. I have not yet repaired the defective balanced cable.

That's how it is with single-ended cables: often you can spend more and get better results (although not all the time). When you go balanced then you get off of the cable game since if the cable is properly built it will simply be correct and no expenditure will yield better results.

If ever there was an argument for balanced operation, getting the cable correct at the signal source has to be it. You can't make up for coloration and losses downstream no matter how good your preamp, amps and speakers are.

Do all phono cables follow this 5 pin din layout? Pin 5 is the earthing cable, ...

Kurosawsa said:

Do all phono cables follow this 5 pin din layout? Pin 5 is the earthing cable, ...

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Yes. All phono cables using this connector are set up this way. Actually pin 3 is the tonearm ground, not pin 5.

The advantage of running a balanced line from the tonearm is no longer having to worry about the 'sound' of the cable. FWIW we (Atma-Sphere) were the first to use this connection in a balanced application as we've been doing balanced line longer than anyone else in high end audio. So we had to figure this out decades ago. The reason to go balanced isn't really lower noise although that is a common benefit.

The raison d'etre is to eliminate colorations from the cable. What this means is you no longer have to have a really expensive cable to get it to sound exactly right. But to do that the cable must be wired right and the phono section must support AES48. It is also helpful for the cable to be low capacitance; no more than about 30pF/foot.

We have seen cable manufacturers add ground wires to balanced phono cables; clearly not knowing what they are doing. Pin 3 of the 5 pin connector will simply be connected via the cable shield to pin 1 of the XLR (at the phono preamp input), which is ground and ignored by the balanced input circuitry, whose job is to amplify what is different between pins 2 and 3 of the XLR.

I see not having to worry about the 'best' sounding cable as an advantage. The balanced line system when properly executed vastly reduces or eliminates altogether colorations from interconnect cables. This is literally what ushered in the age of High Fidelity in the 1950s when balanced lines were adopted by the recording industry.