Balanced vs RCA between amp/preamp

I began my transition from rca to diff balanced kit 2 decades ago.

Same nonsense appears here as back  then (that they are ONLY for long runs) I have heard differences between 0.5m and 1.0m XLRs

Dif balanced is basically 2 totally independent channels (hense doubling the cost), though they often incorporate the same output transformers. 

EVSs new EVS 1200 has 2 separate channels in it whereas most of the similar class D stereo amps do not. Appreciating his knowledge, I bought one

Buyer Beware:  I used to call out the hi end mag editors for giving dif balanced kit to 'reviewers' whose systems are NOT dif balanced. I finally gave up. 

A lot of kit has XLR I/Os but the kit itself is NOT dif balanced, therefore the listener will not hear the difference

RicEVS, wrenth,  and engineears have it correct

audiorusty

Im envious. I always lusted for A-S kit, but was always out of my budget. Perhaps the closest I got was when I had Accoustats with their OTL amps. Did a few modes to the boards + chips and cryoed NOS tubes. Even if the sound was comparable, the Accoustats were affixed directly behind each speaker, designed exclusively for their panels.

Must be cool just to look at them, such a classic design honoring an important era in communications kit that looked like military hardware