Circuit Contamination from EM Radiation (continued)
In mild cases of EM contamination within a given audio component a slight degradation in sonic performance with respect to added distortion and dynamic limiting can result, with the severity thereof directly proportional to the degree of contamination. In worse cases the same can lead to circuit instability, more significant distortion and somewhat erratic behavior of the product. In severe cases (typically high power Class-D amplifiers) the problem may manifest as poor overall product reliability and/or frequent catastrophic failures.
BUYER BEWARE: One should understand that he contaminating EM Radiation being addressed here is comprised of two (2) separate forms – E-Field & M-Field, with each having its own distinct properties and associated treatments uniquely fitted to them and being required for their amelioration. Knowing “which is which” is the fundamental key to their effective treatment, with solid knowledge, background and experience in dealing with them a prerequisite for achieving good results. TDSS' Bob Smith has had many years working in research & development in the areas spanning high power (40KW) amplifier & switching power supply design, AC/DC power converter design and Broadcast Engineering, with special emphasis on remedying such contamination from various EM Radiation sources.
A cursory review of other so-called “upgrade companies” will reveal (regardless of their claims to the contrary) significant shortcomings in this area of expertise. In at least in one instance we have direct knowledge of this fact because at one time we received a previously “upgraded” switching power amplifier from a customer that required fundamental repair of the product’s circuitry. After inspecting the unit they were able to observe the nature of the previously installed upgrades and despite the overall shoddy workmanship thereof, worse yet was the nature of the EM Radiation treatments. Proper treatment would/should have been based on amelioration of the primary E-Field Radiation resulting from the high-speed switching of high DC supply voltages within the unit – which is common to all Class-D power amplifiers.
Conversely, the treatments installed within the amplifier in question were comprised pf virtually nothing other than M-Field treatments. “Ferrite Beads” were inserted in almost every accessible cable & wire, and in addition, a type of “ferrite impregnated” tape was used to wrap every possible wire. Seeing that these treatments would have no appreciable affect on the true, dominant E-Field radiation, the entire effort was of minimal value at.
Worse yet, the addition of ferrite beads when not needed would only work to reduce amplifier performance because the added inductance thereof would serve to significantly limit the speed of current flow to the various sections of the amplifier. In the end, the customer did not receive the improvements that would have otherwise been possible, and may have actually suffered some degradation in performance. Certainly the aforementioned upgrade did nothing to improve amplifier stability because it did fail, with the need for repair being the reason it was sent to TDSS in the first place.
To add insult to injury, the customer paid 300% more to have this service performed over that which we charge for the same (albeit far superior) service, and the provider did nothing to treat any electromechanically-induced noise/distortion problem whatsoever. Finally, due to sloppy workmanship and the unnecessary “spaghetti mess” of it all, we were forced to return the unit to the customer without performing any repairs. This was because there was simply no way to disassemble the "kluge" of wires & tape and then restore it all to it’s prior state after the repair – not to mention the excessive amount of work that would have been required to do so, even if it had been possible. Hopefully, the original upgrade service provider was able to facilitate repair as otherwise the customer would have been left with the equivalent of a very expensive “boat anchor.”
The above scenario only serves to illustrate the point that the matter of EM Radiation amelioration is not a trivial science to be undertaken by the novice. The field is very complex such that insiders of the electronics industry and electrical engineers often refer to it as more of a “black art” rather than a science. Simply knowing which wires to treat and how to treat them can be a very complex task… and there are usually many such wires & cables to consider – not to mention all of the other issues that must be addressed. Furthermore, something as simple as connecting the wrong end of a shielded cable to ground can actually make matters worse, so one absolutely MUST have a very good knowledge and understanding of the field to be certain they are not doing more harm than good.
In light of the above, one would be well advised to thoroughly research any such service provider first before selecting them to provide any similar service in order to be sure that they really do know what they are doing. Anything less is nothing more than an expensive “hack job” assault being perpetrated on an innocent customer’s expensive property.