There is debate on the LSA DIY forum regarding the significance of clean power into LDR devices. I use LDRs in a custom volume control in an AtmaSphere MP-1 preamp. If you can solder and perform basic kit assembly, for about $100 including transformer the Twisted Pear's Placid HD current-shunt regulator is a good choice. Each LDR needs under 10ma, which is adjustable as described in the regulator kit instructions.
BTW, whether used in a passive or active preamp, LDRs sound great relative to a stepped attenuator.
BTW, whether used in a passive or active preamp, LDRs sound great relative to a stepped attenuator.