Excellent selection! As an owner of a Concentra II, bought used here on 'gon not long ago, I rush to welcome you to the JRDG fan club.
My experiences may not be useful, given the difference in the two designs and power supplies. However:
I've found the Concentra II to be so VERY solid/stable that it is decidedly more "indifferent" to cabling changes than other gear I use in other systems. In that respect, switching among cables with the Rowland has been a complete surprise, compared to the other amps and preamps I've used over the years. While you can probably "kill" the glory of the Rowland sound w/ an overly dark or dull cable match, you will probably have a far larger range of decent choices than with other amps/preamps.
The C II has worked very well with Shunyata Phoenix SC, paired with rca ICs. I tried the Phoenix first, and found no need to look on.
As to interconnects, Transparent ICs were just fine, but I moved on. The Ridge Street's Poiemas were better (in MY system), both rca b/c the cdp and tuner in the C II set-up are only single-ended. I've also happily plugged in Ridge St's MSE, rca, w/ the Concentra II.
Some systems won't mate well with silver wires, as you know. I suspect you'd want to tread cautiously, if you are still using the Piegas. I'm running Aerials in the system w/ the Concentra II.
PLEASE let us know how you like the Concerto integrated, and what wire you ultimately pick.
My experiences may not be useful, given the difference in the two designs and power supplies. However:
I've found the Concentra II to be so VERY solid/stable that it is decidedly more "indifferent" to cabling changes than other gear I use in other systems. In that respect, switching among cables with the Rowland has been a complete surprise, compared to the other amps and preamps I've used over the years. While you can probably "kill" the glory of the Rowland sound w/ an overly dark or dull cable match, you will probably have a far larger range of decent choices than with other amps/preamps.
The C II has worked very well with Shunyata Phoenix SC, paired with rca ICs. I tried the Phoenix first, and found no need to look on.
As to interconnects, Transparent ICs were just fine, but I moved on. The Ridge Street's Poiemas were better (in MY system), both rca b/c the cdp and tuner in the C II set-up are only single-ended. I've also happily plugged in Ridge St's MSE, rca, w/ the Concentra II.
Some systems won't mate well with silver wires, as you know. I suspect you'd want to tread cautiously, if you are still using the Piegas. I'm running Aerials in the system w/ the Concentra II.
PLEASE let us know how you like the Concerto integrated, and what wire you ultimately pick.