It might be simpler to just buy a tri-phase cable, but I'm into DIY and so made one up. Here's how:
Ingredients:
You need two 3.5mm mono plugs—I bought metal ones; a metre-and-a-half of shielded cable—I bought 50 ohm because it was fairly flexible; two red and one black 4mm banana plugs—I bought straight ones, but should have bought 90 degree angled ones. You also need a soldering iron, solder and I recommend heat-shrink tubing.
Method:
Cut the cable in half, and strip off about 20cm (8 inches) of the outer sheath, exposing the shield. Separate the shield from each of the internal cables carefully, join the two shields together (for their entire length) and feed the joined shields into a length of heat shrink tubing, leaving about 5mm exposed at the end. Shrink the tubing onto the shield and solder the black banana plug to its exposed end—I don't need to explain to place the cover over the heat-shrinked shield first ...
Take the two inner cables, and solder the end of each to a red banana plug.
Now there are two cables with 'open' ends, and two 3.5mm plugs left, one for each. Solder the open ends of the two cables—the bits with shield intact around the core—to the 3.5mm plugs. The inner core must be soldered to the tip of the plug, the shield to the longer part (called the ring). If the core is 'thin', strengthen it by applying some heat shrink along its length before soldering.
And there you have it. I have had great success with one of the red ends connected to just one of the E-STIM straps around my cock shaft, and the two plugs—the black and the red—connected to an anally inserted E-STIM moaner, the red plug to the centre.
Enjoy!!
(Or, if it's all too hard, order a tri-phase cable now!)
Update: you may be able to use ordinary unshielded two-core cable. And try it with the black plug to the centre too!
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