Placette RCV Passive Pre between pre and power amplifiers?

agree with George, up to a point.

it will depend on the impedance match and output drive between your CDP, and the Placette RVC, and then the same with your amps.

the odds are that you will prefer the Placette RVC to your active preamp in the signal path. but you really cannot 100% predict exactl how it will work or whether you like it. assuming you are buying the Placette new there is typically a 30 day money back trial period.

from 2001 to 2005 i used a balanced Placette RVC with a custom passive switchbox made by Jena Labs. it bettered my $15k Mark Levinson No.32 preamp to begin with, and then a number of other active preamps. it wasn't until i tried the (now $40k) darTZeel NHB-18NS preamp that i found a better pre than the Placette.

good luck.

What George said, +1.    I had a Placette Passive Linestage and loved the transparency, over the ARC SP9 and SP14, that came before, though neither did anything, "wrong".    The only problem I had, with the passive, related to the inefficiency of the rest of my system.    That only reared it’s head, when listening to some sessions, recorded at lower levels.    My love for LOMC carts, Magnepans and tubed main amps, all contributed to the shortcoming.    Anyone that didn’t require the SPLs(I try for live), wouldn’t have had an issue.    With a majority of recordings; the presentation was wonderful.    Definitely: give it a try, without the pre.

Another option is the schiit freya-s
https://www.schiit.com/products/freya-s

Set the freya-s to passive and insert it to the input or tape loop of your ARC LS-5II.

btw:  Think about the extra interconnect pair(s, depending on configuration), if you leave the ARC pre, in the system.   More connections and wires, never seem to help one's presentation.