LCR phono stages we know about

Maybe you could explain a what LCR phono stages are.

Mordante et al, I apologize for not defining the acronym. I thought most analog aficionados would know about LCR RIAA circuits. But here goes a definition:
In analog history, nearly every commercial phono stage has been based on using RC filters to achieve RIAA equalization. An RC filter is one that uses resistors and capacitors to achieve each of the three 6db per octave "shelves" in the frequency response that constitute an RIAA correction. Most such RC-based RIAA networks require the use of a fairly high value resistor in series with the phono signal coming out of the first gain stage. And some require the use of at least one capacitor in series with the signal, as well. The advantage of an LCR network, used to achieve the exact same RIAA correction, is that it places only an inductor in series with the system, which has very low DC resistance compared to the resistor mandated in RC type RIAA networks. Capacitors and resistors are used as well, but all of these are in parallel with the signal, connected to ground. Theoretically that does less "damage" to the signal, where "damage" can mean different things to different audiophiles. Proponents of LCR type RIAA correction circuits believe that they sound better, pure and simple. However, implementing such a network presents a lot of problems to the designer. Thus = expensive.

Yes, JFrech, I knew that Allnic (in the H3000 and H1500) make LCR type phono stages, and I knew about Zanden. Did not know about Ypsilon being LCR type. All of these are VERY expensive. (Well, the Allnic H1500 is not too far off the charts.) Have you heard any of these 3? In fact, I would love to hear from anyone who went from a very fine RC type phono stage to a top of the line LCR type. I would also like to hear from anyone who has actually listened to any LCR type phono and who has an opinion about the advantages based on real world experience.

LCR phono stages implement the RIAA equalization using passive components (inductors (L), Capacitors, and Resistors) between the active gain stages, in much the same manner as a loudspeaker crossover, instead of doing the equalization within an active stage. Some preamps use both techniques, one for the bass boost, and another for the treble attenuation.

That's not quite correct or at least possibly confusing as written, Sqlsavior.
LCR vs RC has nothing to do with active vs passive RIAA. Either technique can be implemented in a passive RIAA filter. It's just a matter of how the filter is created, with inductors in series with the signal vs with Rs and Cs in series/parallel.

Not all RC RIAA phono pre's place a large value resistor in series with the signal. I have a fully differential phono pre designed by Kevin Carter of K&K Audio that does not. The large value resistors (and caps for that matter) are all shunt connected, not series. In its first incarnation this was not the case. This will get a little technical here but bear with me. The input stage consists of a pair of vacuum tube/JFET (now MOSFET) cascodes. In the original design the tubes had plate loads and the plates were direct coupled though 33K resistors to the grids of the driver tube (the series connection). With a later redesign the plate load resistors were replaced with Constant Current Sources (cascoded MOSFETs). This required changing the 33K resistors from a series connection to a shunt connection (from the plate to ground) leaving just a 10 Ohm grid stopper in the signal path.

What does all this mean for the sonics? A way more dynamic sound, macro and micro. A much better sense of touch. It brings closer the sense of real music being plaid by real musicians. I heard this change with everything else in my system the same. So I can say without reservation that removing that large series resistor makes for a big difference.

BTW, Kevin's latest generation of his single ended parallel feed phono pre the Maxed Out uses this same arrangement. You don't have to opt for a LCR design to reap these benefits.