Can anyone explain cable risers?

Also, running wires parallel to each other and in close proximity over a distance is generally not a good idea due to em field interaction and risers are one way to avoid that.

YES but the best explanation will come from your friendly neighborhood voodoo doctor.

They do nothing except seperate you from your money. It's called wealth transfer.
Cheers

The interaction that occurs is when something like a synthetic carpet has cables laying on them. The synthetic carpets properties are similar to those used in cable jackets and thus, compete with and interfere with those fields mentioned that travel with the cables signal. They simply smear the signal.

Yes, they can be measured so it stands to reason that if something is nearby, let alone parallel with and touchung a cable, can interact with it, then it can mess with it.

To what extent is debatable but if you have synthetic carpets, then go the extra mile to get them away from the carpet but you need not pay through the nose to do so.

I'm lucky in that my Mapleshade Double Helix speaker cables are so taut that they are easily suspended with nothing more than themselves and whatever nearby is handy.

If you have wool carpets or wood flooring, I wouldn't give it any consideration.

All the best,
Nonoise