Master/Slave Link Summary

[hardcore]

I once had this same concern.  Personally, I do not hear a difference between left and right channels.  I am running RCA to RCA with a trigger cable that allows me to use inputs on both units.  Since my 440 Pro is essentially two 220s, I even tried swapping the two 220s (ie.  swapping master/companion) to see if it sounded any different.  It did not.  Intellectually, it still seems to be a valid concern....  If different digital cables produce different sound, then how could it not produce a difference between left and right channels?  But to my ears in my system, I am content that there is no sonic impact of this.

I had the same left-right imbalance concern when considering if I should upgrade from a 250 to a dual-mono 1000. But it turned out it was no issue.

My theory for why the XLR sounds better, and why there isn't a problem of 'left-right balance', is because of "ground loops". Any cable that inter-connects two components which are grounded separately, becomes a potential path for ground loop noise. Ground loops will introduce noise into the ground plane of *both* devices, so in a dual-mono, it affects both Master & Companion, so 'left-right balanced' in a way.

Using the XLR input which is transformer isolated, and avoiding using any other electrical cable going between Master & Companion, avoids this extra path for a ground loop between Master & Companion.

And by the way, better not try to ground-lift the Devialet, because in the manual it explicitly says that the ground connection in the power cord is required.