Impedence and capacitance for a Supex 900 Super

The coil resistance of my Supex 900 Super is 3.5 ohms and the recommended loading is between 20-500 ohms.

I have this same cartridge with the original paperwork, and yes, the impedance is 3.5 ohms.

I would procede with the above suggestions then. Sorry for the delay in getting back to you. Sean
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I believe this is the earlier 900 Super then. There is no "e" on the front of the cartridge - it just says Supex 900 Super.

I just found a review and comments regarding a Supex 900E Super in the same magazine ( they covered 54 different cartridges at one time !!! ). This one has different loading recommendations. He also makes mention of yet ANOTHER earlier 900 Super. Which 900 do you have ? Sean
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I have information on the Supex SD 900, which in the notes says that it is very similar to the Supex SD 900 Super.

The reviewer ( J. Peter Moncrieff from International Audio Review ) states that the internal resistance of the cartridge is 7 ohms, stating that this is quite a bit higher than some other MC's. There is no mention of what resistance he used to load the cartridge with. With the factory recommended loading ( whatever that is ), it shows an ever rising response from the midrange up, a slight dip or "plateau" in the extreme upper mids / lower treble and then two bigger peaks way up top.

To compensate for the rise, IAR recommended "overcompensation" by using 4400 pF of loading. This drastically lowered the noise and actually produced a roll-off from the midrange up. He states that this helped compensate for what they thought was a "sizzly" top end while also trying to minimize the noticeable "plateau" that occurs in the middle of the rising response. Moncrieff tried other loading and felt this worked best.

Judging by the frequency response curves, i would probably try starting at about 800 pF total ( taking into account arm wiring, interconnects and phono stage adjustments ) and work your way up from there. The higher that you go on capacitance, the less apparent treble you will have. You should be able to find a balance that should blend with your personal tastes and system.

While this flies in the face of what Joe stated regarding capacitance and MC's, i'm simply relaying what was printed 20+ years ago. Sean
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start at 30 ohms load - after that follw joe's res.
cheers - siver upstream is good.

Capacitance is not an issue for MC cartridges; only for MM. Best to set it as low as possible for other reasons. For impedance, the mfr's recommendation was 100 ohms, but many of the reviewers liked 1000 ohms or even 47K ohm. After you set the tracking angle and tracking force, try all three. The one that gives you the most realistic soundstage with good dynamics is the way to go. If the highs ever get in your face, then set the impedance lower. NEVER run the cartrige below 1.5 gram tracking force.
Best of luck,
Joe