What's the benefit of balanced tonearm cables?


My phone stage (bat vkp10) has xlr and rca inputs. bat vk50se preamp. I use all balanced cables for everything except the tonearm cable.

What's the benefit between your cartrige to phone stage?

Thanks!
128x128jfrech
The reason a balanced connection can have no cable artifact is the fact that the signal travels in a twisted pair within a shield (BTW this is how the signal travels in the tone arm- the arm itself being the shield).

The shield is there for shielding and does not have anything at all to do with the signal otherwise. The signal occurs in the twisted pair- the output of one is in respect to the other, rather than ground which is the shield.

In a single-ended setup, the minus output of the cartridge becomes the shield. In this way signal current is passed through the shield and is vulnerable to noise issues. Usually these manifest as intermodulations (colorations) rather than actual hiss or buzz.

(If an RCA is used as a balanced connection, which is dicey due to the grounding scheme, the result is that it will be prone to noise pickup because of the imbalanced introduced by the connector itself. If you doubt me, just touch the shield connection of the RCA on the preamp and see what you hear. BTW if you hear nothing then its not being used in the balanced mode- this is why I say you either have balanced or you don't and there are no in-betweens.)

This is why a balanced line interconnect can be rather inexpensive and will easily keep up with the most expensive single-ended cable no worries. There are of course other advantages, some of which have been discussed here. There really is no advantage to running single-ended in this situation, keeping in mind we are talking about how the cable behaves and not really how the phono section behaves, although its a fact that a fully differential balanced phono section has advantages too.

Conclusions:
all cartridges are balanced.
the cable thus can be inexpensive.
the cost of the cable is part of the cost of the system.
So balanced line can actually be less expensive, quieter and less colored than a single-ended setup.
Again this is so far just about the cable and its advantages. This is not about the behavior of the preamp, although that certainly plays a role- perhaps a topic for another thread?
If an RCA is used as a balanced connection, which is dicey due to the grounding scheme, the result is that it will be prone to noise pickup because of the imbalanced introduced by the connector itself.
IME using a RCA plug to terminate a balanced phono line (twisted pair with separately grounded shield) is not as problematic as you suggest. In an ideal world one would want to use XLRs. Where that isn't practical using a RCA termination won't be the end of the world. I am assuming the RCA jack connects to a "floating" transformer winding or a true diff. input.

I can clearly hear the differences in balanced cable....are you saying that balanced cables sound alike?
If an RCA is used as a balanced connection, which is dicey due to the grounding scheme, the result is that it will be prone to noise pickup because of the imbalanced introduced by the connector itself.
IME using a RCA plug to terminate a balanced phono line (twisted pair with separately grounded shield) is not as problematic as you suggest. In an ideal world one would want to use XLRs. Where that isn't practical using a RCA termination won't be the end of the world. I am assuming the RCA jack connects to a "floating" transformer winding or a true diff. input.

Balanced signals have greatly reduced common mode noise, but that’s not what I would call a cable artifact, so much as atmospheric, or environmental.

What they can completely eliminate is ground loop contamination, and crosstalk.  Cross talk COULD Be caused by a non-zero ohm ground.

So three things:

  • Improved common-mode noise rejection
  • Eliminated ground loop
  • Reduced L to R cross talk

But eliminate cable effects? That’s a bit of a stretch for me. It does not cancel out capacitance, inductance or resistance. 



Best,


Erik