SME 20/2 SME V or Triplanar VII?

Thom,

I have my XV-1s loaded @ 500 ohms. I tried 100 originally but found 500 best. I also load most of my other cartridges @ 500 ohms including the Condor & the Eminent. I experimented w. all cartridges & found that the each one performed best @ 500 ohms. Can it at times be preamp specific. I plug in different resistors into my preamp. I have 100, 200, 500 & 100 & 47. Should I order more before the Universe gets here? I found the low loads to be closed in.

Dgad,

The very low impedance values Thom is discussing assume the use of stepup transformers. When I used stepups I also used sub-100 ohm values, and found that great precision was necessary to optimize the performance of any LOMC.

FWIW, our new high gain phono stage + the .24mv UNIverse are happiest somewhere around 150-225 ohms. If I go any lower it sounds exactly as you described, closed in or muffled. Cello's Supratek Grange + UNIverse sounded best around 100-125 ohms, IIRC.

Assuming your phono stage doesn't include stepups, you might be fine at either 100 or 200. If those aren't optimal I'd bet on something in between.

Dougdeacon & Thom,

I guess you are referring to the resistive load on the Coil as opposed to the load. Correct me if I am wrong in describing it. I am using a battery powered solid state unit so I probably will load it @ 100 or 200. How long do you need for break in?

Thanks for stepping in, Doug.

Also, note that the rule of parallel resistors applies, but in the case of two largely different resistor values (like 47K and 500 ohms), the net parallel resistance is for all intents and purposes that of the lower value resistor.

Cheers,
Thom @ Galibier

Thom's right about dual paralleled resistors, which I did use extensively with my stepups. The math is easy though.

Dgad,

My MC phono stage is also solid state, so those numbers should put you in the same ballpark as me. (One possible difference is the native input impedance on the inputs. Mine is around 1500 ohms without any resistors, FWIW.)

If you're referring to break-in on the UNIverse, my experience (with four of them) is that they made most of their progress in the first 5-10 hours and changed very little after 20-25. They were bass- and dynamics-shy OOTB, but they opened up and then stabilized very quickly.

No other cartridge I've had broke in so quickly and easily. The Airy 2 needed 75+ hours to open up. OTOH, the Airy 3 needed 150+ hours to calm down. The Shelter 901 needed 300 hours before it stopped sounding like nails on a blackboard.

If you're asking about break-in on the resistors I have no idea. Considering the levels involved, it's probably decades!