I am currently using a Promitheus Ref 4 TVC a with an older pair of passive friendly DNA-1 monoblocks. The Ref 4 is much better in every respect than either the McCormack TLC-1 or Endler resistor based volume controls I used previously. The Ref 4/McCormack seems to be a pretty nice combination to me. No problems with impedance mismatch, insufficient gain, or cable length with this option. I have rather insensitive speackers (Magneplanar 1.6) and rarely go beyond 1 o'clock on the volume. I would suggest you consider the Promitheus along with the Placette and Sonic Euphoria. These are all good values and resale should be good. One might do some A/B comparison and keep the best match in your system.