How important is the cable between the SUT and phono pre?

@jasonbourne52, it's not quite that simple for MM as increasing capacitance will also move the resonant frequency down, depending on the electrical characteristics of the generator, of course.  This is why on a cartridge like the AT150MLX, if you want flat response, the cartridge cannot see more than 150pF.  Also why that cartridge has such a maligned reputation for exaggerated HF response.

@mulveling, looking at transformer equivalent circuits I don't see reflected capacitance.  Reflect impedance, reflected leakage inductance, but not capacitance.  Do you have cite for this?

@billwojo, capacitance on the secondary with load R will form a zobel, which can tune the response of the transformer.  For best performance every SUT should be tuned this way, but as it is cartridge, transformer, and upstream phono stage dependent, it's not practical for the average person.  Just know that changing C on the secondary can have an audible effect, but it's to do with the transformer response itself.  

At the bottom of this page is a tech note from Morgan Jones: https://www.sowter.co.uk/specs/8055.htm

Impedance != capacitance.  

Hi @imhififan, he's basically explaining a zobel like I mention above, and some generic advice that may or may not fit a circumstance.   However, transformers do not reflect secondary load C to the primary.   

Would love to see a cite with a detailed technical explanation.  I can’t find one, equivalent models I can find don’t show it, and a couple EEs I’ve talked to say it doesn’t.  Repeating a formula is not an explanation.  

Thank you for the reference.  Section 1.2.4 is in regard to inter- and intra-winding capacitance and electro-static shielding, which I understand.  While Figure 16 depicts secondary load C as CL, I do not see a reference to it in the text.  This section doesn’t seem to address reflected C.  

No, that's not the problem I was having.  Worked through it with a friend and see that I was not correct.  Regardless, something that actually explains it would be beneficial.  I like to enhance my understanding of things, not just parrot what someone says because they said it. 

Thanks, but as I’ve said a couple times now that wasn’t the issue.