Ferrite Cores for Power cords


I am new to DIY and just made two power cords based on the Oyaide Tunami cable and Furutech connectors I purchased from vhaudio. My understanding is that I can possibly enhance the performance of these power cords by fixing ferrite core cylinders/boxes onto these cords. I will highly appreciate your advice/comments on the following regarding ferrite cores :

- Where can I buy them and which are the good ones/brands ? Any online source for buying these will be great.
- Should I attach them to both ends of power cords or only one end is enough ?
- Is there anything else I should know when I use them to derive maximum performance from the power cords ?
- Is it normal to attach the ferrite cores on interconnects and speaker cables as well

Please share your experiences.

Thanks in advance.
wilfredt
There are a lot of things I would like to do with the incoming power but that will have to wait. Two very young kids will put a stop to most anything that requires a lot of time on a project. I would like to try better sheilded romex on my dedicated lines eventually and I know some who have done this with good results.
Two days ago I put some ferrite clamps on my Reality cable ic's from the cdp to pre. Two clamps coming out and one clamp going in. They are not coming off of these ic's and I did not think to try them again until reading this post. These ic's are fairly new in my system and they do not have a lot of insulation/shielding around them. The high frequency did not roll off and the mid range became more coherent. Less noise less grain. One thing I did notice is that the ferrite has to fit fairly tight over the cable. These probably won't work on all ic's but the ones that do not have a lot of insulation or shielding may benefit with ferrite clamps. It Would have been interesting to put these around the Anti Cable ic's I was using at one time. Audio Metallurgy GA-0's use a magnet all the way down the middle of this ic and that seemed to roll the highs off for me too much. They are real good for a bright system. Still acts as a ferrite however.
There use to be Red Rollers, but I think the company is out of business. Appart from those used in the expensive Siltech line of cables, the Red Rollers are the only ferrites I could stand. They are quieter but at a high price in terms of the pace of the music. I retained a few Red Rollers for use in a dedicated ground but have heard they are useless on a ground.
Versalab "Red Rollers" are missed by Me, I got 6 in the '90's...lost one somehow. Adioquest made "Big Blockers", but not offered anymore.
Versalab also made "Split-rollers". I wanna find a couple, no inconvenience(struggle) to get past the bigger plug moldings on PCs.
In addition to my 5 Red Rollers, I am using the largest ones from Parts Express here and there. Under $4. bucks ea.
I consider them essential for Line Level connects.
Anyone got any Versalab "Split-Rollers" for sale?

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