Copied from my post over at Audio Asylum. It is quoting myself so I am certain it is OK. Due to request for exact discription of make the pigtail here it is:
AA posted last week:
The idea is to add a 'pig tail of wire to the wiring, generally on the negative pole.
This is to improve the sound.
The places to do this are on A/C wiring at the receptical on the 'neutral side (and never on the 'hot' 120V side.)
Or at the amplifer five way binding posts. (It can also be put on the ground side of interconnects)
Various forms are for sale commercially for $30 a pair.
From reading about those, I decided to add the ferrite as a 'load' at the end of the wire. The original idea was just the wire was all, hanging in space going nowhere. Then the first adaptation made the wire into a bit more substantial blob. My further take on this puts a ferrite blob on the end of the wire.
Appearance:
The wire is any wire. I use a 12 gauge teflon insulated silver plated wire because i have a lot of it. And am actually using up scrap from a 700 ft spool of it.
The ferrites are 1 inch long, cylindrical shaped 1/2 inch diameter ferrite tubes. (these i have because they are a perfect fit over A/C 14 gauge three wire power cords)
I take 11" of wire, and peel off 5 inches of the insulation from one end.
I place the wire in the hole on the ferrite up to 1/4 inch from the end of the stripped portion. So about 6" of shilded wire, and 1/4 inch of bare wire is out one end of the ferrite, and the remaining bare wire out the other end of the ferrite barrel. I bend the bare wire back up and around the outside of the ferrite back to the top of the ferrite where it meets the shielded wire. I wrap the bare wire to the 1/4 inch bare portion at the top, pulling VERY tightly on the wire as I wrap it around together (using the needlenose pliers leverage to tension the wire) so the wire is now very tightly holding the ferrite. I wrap the bare end around the shielded wire about three turns, then cut off the rest of the bare wire.
So now i have a single shielded wire, six inches long with the ferrite at the end connected to the wire and the ferrite is electrically bonded to the wire. (I use the pliers to smooth the remaining bare end to the area the wires are twisted together.
Then I take some Teflon plumbers tape (blue thicker teflon) And I wrap up the ferrite, and the bare wire holding it. So the teflon completey covers the bare metal. both wire and ferrite.
The result is a (smokers pipe shaped) device. The end tip of the shielded wire is striped for about 1/2 inch.
Now my tweak is ready to use.
You need at least two. One for each negative speaker terminal on the amp. Most amps have five way binding posts, and use the one that is not on the speaker wires. So my wires use the screw down, and leave the banana free, so I stuck the tweak in a banana connector and just plugged it in.
I have added six more, so the positive at the amp also has one, and at the speaker the low input, and the mid/high input(biwired) each have one. This is just me playing around. As the first pair really do the magic. and the added ones just are minor, but they do NOT degrade the sound. (like so many tweaks where a little is good, but a lot is bad)
i also have one on each of the four dedicated A/C lines.
(On interconnects did not do much good, Only made sound fuzzy)
All I can say is it does help.
