I just had my first small adventure in capacitance loading. I have had an Audio Technica AT150MLX for about 3 years. I always used it with a Cambridge 640P which, to my knowledge, adds no capacitance to the load. I dunno, maybe it's set at 100 pF. Anyway, it's non-adjustable and I just plugged and played.
This week I got a Jolida JD 9A, a tubed phono stage with a battery of DIP switches. Three are for setting gain level, four per channel are for setting resistance load from 100 to 1000 ohms for LOMC's, and four per channel are for setting capacitance for MMs. Audio Technica recommends that the AT150MLX see a load "between 100 and 200 pf." According to Technics there is about 100 pF in my turntable's built-in interconnect. Last night I set the Jolida's capacitance to 100 pF for a total of 200. I listened for about 3 hrs and felt that there was just a little too much emphasis on body resonance and not quite enough air and transient attack. This morning I decided to turn all the capacitance off. When the needle hit the vinyl it was immediately apparent that this was a bit low--too much transient attack and air, not enough body.
So I set the DIP switches to 47pF, for a total capacitive load of 147pF, and this was *just right*. It is well balanced. Transients are sharp and the Jolida and the NOS tubes I stuck in there are showing their stuff with plenty of jump, while there is ambience and resonance aplenty with a very rich presentation.
Now YMMV, but for my rig, with this cart, interconnect, and preamp, 100 pF was too little and 200 was too much. Fortunately there was a 47pF setting which dialed in a very addictive sound. The best validation is that my wife likes it as well. Women have better HF sensitivity, so if the capacitance were too low it'd drive her out of the room (and makes my shoulders go up as well).
I was originally considering a Musical Surroundings Phonomena II, but the deal-killer was that in MM mode you can only set the capacitance to either 200 or 300 pF on that unit. As I found out today, either of those settings would have been too much and I made the right decision for my situation.
Update 7 hours later: Man, you just have to keep your ears on all the interdependencies at all times. I just swapped out the entry level aftermarket power cord I installed on the Jolida phono stage for a 2006 PS Audio Prelude power cord, and I'm getting a richer, fuller sound with more bottom to the tonal balance (which I like). So always remember, it doesn't all come down to capacitance (or with LOMC's, impedance).