Wisdom in mind,   enthusiasm at heart.

Master-3
Real Balanced ACSS  Power Amp
Supports XLR and ACSS input

How to connect the preamp only had the RCA output :
      Master-3 is a real balanced design power amp, so even connect the RCA output from preamp, can conversion to balanced output in the amp inside ,without any extra circuit board .
     While connect to the RCA output preamp, we are advice applied the RCA to XLR cable as below diagram . This is can be better than use the RCA- XLR adaptor and modify the Master 3 had RCA input sockets .