Hi Marco,
Your undergoing the same experiment I went through a new of months ago, in that your trying to correctly get the SC35C to "see" that correct amount of capacitance. My M55E likes to see 450-500 pf according to the Shure website. All connecting leads carry a certain amount of capacitance, I did a quick and dirty calculation based on an audit on everything that sits between your cartridge pins and the the RCA lead going into your Croft phono stage, which unfortunately has no facility to use RCA loading plugs. The components between your cartridge and the croft MM phonostage include :-
(These are the known values of my own systems personal components, yours will be different).
15pf per channel = 30 pf intrinsic wiring of the tonearm
10pf per RCA = 10 pf RCA
60pf tonearm cable = 60 pf tonearm cable
10pf cartridge tags+leads = 10 pf (SPECULATION)
20pf for tonearm connector = 20 pf (SPECULATION)
so this equals ~115pf of capacitance, so we are approximately 335 pf short, so you use two 335pf RCA loading plugs for the M55E to "SEE" its required 450pf. This will of course be different for the SC35C (I don't know what it likes to "SEE", pf wise), it will also differ because we have different RCA plugs, tonearm cables and intrinsic wiring of tonearms. You need to individually work out each components pf level and then deduct that from the SC35C's suggested "SEEN" capacitance. Your RCA values will be the difference between the two values. This is a more accurate way of "tuning" the thing by ear, of course you may prefer it that way. I hope this helps.
Finally, did you do your loading tests at the same time as trialling the Houdini? If so, how can you confidently attribute your experiences to the Houdini and not the optimal capacitance loading? Just a thought.....
SS
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