Mark Levinson No 52 Preamp phono stage custom loading

I learned here last year, it takes some research to get it. Then, if like me, I forget what I learned.

Take it apart, look at it, see how they physically change, then: STOP!
research your cartridge, then change settings.

47K is for the majority of MM cartridges, it’s like PASS on a SUT if running a MM thru it.

The lower ohm settings are for various low output MC cartridges (LOMC), each having two important specs:

signal strength ( .. mV;) needs boosting (x factor)

internal resistance ( .. ohms) needs/becomes boosted (relative to x factor squared)
this is the trickiest part. result is what resistance is ’shown to’ the MM input.

the ’starting goal’ for ’shown impedance’ is: cartridge internal impedance multiplied by 10. then, up or down from there.

i.e. my AT33PTG/II has signal strength .3mV and internal resistance of 10 ohms.

I need an x factor high enough to get the signal high enough for my MM Phono input
and, I would like to have the impedance shown to the MM 47k input to be around 100 ohms.

x factor effects the impedance by a formula involving x-factor squared.

I better stop now, anyway, take it apart!

Perhaps similar to No.32 using a pair of screw terminals?
Mark Levinson Nº32 Phono Manual

@imhififan Thank you very helpful!

It dawned on me that I should be able to also set the load to the option of 47K, and then use loading plugs. Example 900 ohm resistor used on a loading plug (1 male RCA to dual female RCA) would give me ~900 ohm resistive load?

what are your cartridge(s) signal strength and internal resistance?

SS Hyperion. I want to be able to resistive load between 470 and 1000 ohms. Loading plugs using 47K stage setting would be easier maybe to find what I like. Then I would use the internal screw terminals (if they exist in the No 52).