Choke selection

[cubanpete]

I'm planning an 18 watt Orange OR120 build and want to explore using the Hoffman Plexi 6v6 power supply and power amp. So far, I have back calculated what the cutoff frequencies are for an OR120 at each filter node and compared them to the Plexi 6V6.

So far it looks like I can just basically marry an OR120 front end with the Plexi 6v6 backend but I'm uncertain about the choke selection. Hoffman's BOM specifies a 4H choke which is followed by a 20 uF cap. When I do the math that is a resonant frequency of 17.8 Hz. Find specs on the OR120 choke has been difficult so using the Marshall 1959 specs (3H choke followed by 50 uF total capacitance) the resonant frequency is 13 Hz.

Everything I'm reading by Merlin Blencowe suggests that a choke and capacitor should be selected such that the resonant frequency is below 10 Hz. To do that with the Plexi 6v6, that would mean either sizing up a choke and/or increasing the downstream capacitance.

Upsizing the capacitor would be easier since the chassis is pre-drilled however that would mean a 40 uF reservoir cap, and a 4H choke, followed by a 50 uf smoothing cap. This seems odd to me.

Should I make this change 50 uF, stay with the Plexi 6v6 back end and keep the 20 uF cap, use a different choke rated for a higher inductance, or just replace it with a resistor? All I want is clean power and to avoid excessive hum and/or motorboating.