DIAPASON March 1997

For years, the “sound" from cables has provided the scientific community with some
unresolved problems. All the hypotheses have been considered and all the theories examined.
All except one, that of "interface micro-discharge", recently developed by Pierre Johannet,
of the Research and Development section of EDF (French Electricity Board).
This new and fundamental theory can be applied to all electronic components.
It’s wide range of application should revolutionise the world of high fidelity
by explaining all of the paradoxes.

PhotoFor orthodox physicists, the field of high fidelity has become very irritating. There is practically no longer any correlation between what is measured and what is heard, and the international “top of the range” market has a tendency to develop based on increasingly dangerous esoteric concepts. Even the biggest brand names are following the trend. The profusion of 'special' cables sometimes with very high price-tags, well illustrates these irrational tendencies which are a challenge to scientists. Obviously it is possible to smile in commiseration. However, today the phenomenon has reached such a point that we can no longer avoid it without a certain dose of bad will.
After having examined various scientific hypotheses, one researcher, Pierre Johannet, has just made a crucial discovery which finally provides the key to all those paradoxes which have dogged Hi-fi for years. His reflection stemmed from the most disturbing of these paradoxes, especially for an engineer working for EDF, how do we explain the audible interference produced by the mains cable of a piece of equipment - only one metre long - when it comes after miles of electricity line. Such a phenomenon does seem most absurd. It appears so contrary to reason that one might be tempted to deny it. It was while trying to fully understand it that Pierre Johannet developed his theory. This theory, which is based on “interface micro-discharge”, is as simple as are all good ideas.

It states that wherever current passes through a conductor, molecular scale micro-discharges are produced within the conductor/insulation interface.


These micro-discharges are heard as short clicks. As opposed to static electricity, the clicks are audible because they are generated and modulated by the audio signal. The sounds are like high-frequency peaks, which disappear and reappear along the whole cable length. Hence their audible influence along the last few metres. A specially treated cable (patented by EDF) to neutralise the interference immediately revealed in spectacular fashion the validity of this theory.

Loudspeaker and modulation cables are also subject to the micro-discharge phenomenon. Their intensity depends on several factors: firstly on electrical current but also on the nature of the dielectric, on it’s more or less close contact with the conductor, and on the state of the conductor’s surface. This point is paramount as it finally explains why, given equal resistance, there is a difference in 'sound' according to different metals: copper, silver, gold etc. Whenever current passes through them, however weak, all the electronic components (with the exception of tubes inside a vacuum) become the centre of micro-discharge of greater or lesser intensity. The field of application for Pierre Johannet's theory is therefore immense.

It should extend beyond the field of high fidelity into that of video, micro-computing and metrology.

In the hi-fi context, this theory allows us to understand a multitude of well-known, but poorly-understood phenomena, such as the audible effect of vibrations on purely electronic links inside amplifiers. The micro-discharges are indeed very sensitive to the slightest vibrations. They are also reactive to the degree of air humidity and temperature... The scale of their influence seems so vast that we might wonder why their existence hasn't been discovered earlier. Most pernicious, the main reason is that the means which should be used to combat them actually generate those effects themselves. This occurs especially in the case of condensers which are connected to the end of certain cables. It is difficult to isolate an illness which is caused by the remedy itself!

All that is left is to elaborate the correct remedies. Pierre Johannet has discovered a few of them and their impressive audible effectiveness has convinced us. They have been patented by EDF and are certain to interest a number of manufacturers. We listened to a simple hi-fi system which had been treated against the effects of micro-discharges and we were amazed by the quality, far superior to anything achieved up to now. We therefore believe that this discovery will remove the mysticism surrounding hi-fi and will provide the means to make long hoped for progress.

We want to thank M. Pierre Johannet and all the persons who took part in these research and discoveries (MDI and other) very helpfull for the Hi-Fi community in order to have a better understanding of these phenomena, and so, to improve the musical results of Hi-Fi systems in an unexpected way.