I have completed the ferrite experiments this weekend. My conclusion? Used in moderation, these ferrite rings can reduce interference and have beneficial sonic effects in the following situations:
1.) on DC leads, esp. when on base and collector leads of transistors in preamps, amps, and digital circuitry. Using the smallest size MECs were sufficient for this.
2.) on OTA digital cables, the smallest size MEC (MSFC4EX 4-5 mmm dia.) positioned close to the plugs of the output end. This will hinder sliding of + and - cable against one another, and change the impedance of OTA protective tubing. The sonic improvement is noticeable esp. in the rise and fall of signals, and there are also noticeable improvements in clarity. I detected no negative losses in this application.
3.) another possible route of entry for ferrite rings is at the output end of the speaker cables. Speaker leads may happen to resonate at interfering frequencies and thereby interfereence potential. An 8-ft length of OTA speaker lead is resonant at approximately 30 MHz. Using one MFSC4EX ferrite ring each on + and - leads to speaker cabinets had about the same effect as an ENACOM loudspeaker device. But I imagine that this trick works best with properly stabilized amplifiers.
4.) The larger sizes of ferrite rings (up to MSFC10KEX and 13KEX) were used on OTA power cables with positive results. This was the only time I used the larger magnets. I had best results positioning them near the IEC or inside the chassis of the component when possible.
Of course, the optimum values of ferrite rings should be determined experimentally for each system. It took me a long time to find the right values for my system. Having many ferrite rings at hand, it was easy for me to play with different combinations. Using them on analog interconnects between components, there was a very noticeable loss in stage response, and I would not recommend the use of ferrite on Stratos analog interconnects at all. The ferrite rings act like a resistor, and excessive values of resistance can easily impair high-frequency and transient response. That is why I recommend moderation in ferrite use, and the smaller sizes to begin with.
Dekay, I do not know any MEC website: I ordered them from a German electronics supplier. Sorry to hear about your turntable accident. Shortening the length of your phono lead with OTA will bring some more urgency to your set-up, and probably differentiate your LP sound even further from your CD sound. However, as I well know, this arrangement can certainly expose certain problems with your existing set-up that were previously inaudible. In my own case, I had to resort to grounded Mu-Metal (high permeable Nickel Iron) shields and a completely reworked ground and power scheme. Good luck.
