Balanced vs RCA preamps

Balanced interface is superior to single ended, not matched impedance RCA (or DIN) one, because:

1) truly balanced (not pseudo) interface has common mode noise rejection, which eliminates / reduces noise between two connected devices chassis / gnds, RCA (or unbalanced DIN), transfer all noise to the signal. 

2) balanced interface, originally designed for 600 Ohm driver / receiver impedance match, eliminates problem of time delayed signal reflections from original signal, thus enables long cables w/o tangible signal quality loss).

3) balancing in RCA or other single ended interconnects can be achieved by adding isolating / balancing transformers, but good performing transformer is costly. 

@68pete "Just because you have balanced input and out puts does not mean the unit is full balanced!” +1

XLR isn’t only balancing solution possible! I designed “balanced interconnect” by adding out and in fully isolating ground transformers, typ 50Ohm unbal. <=> 600Ohm bal. systems with RCA/DIN unbalanced outs and ins with excellent results!