NEW: Book on Current-Drive of Loudspeakers Published

[ETM]

Hello, all pursuers of natural sound

This is to announce the publication of my new book:

Current-Driving of Loudspeakers:
Remedy to the Fundamental Fallacy of Sound Reproduction Technology
by Esa Meriläinen.



Softcover, 342 pages, available at Amazon.com.


Short introduction:
Why have the basic laws of electrodynamics been ignored in the design of all loudspeaker operations? An astounding exposure of the flaws of voltage drive and a thorough, groundbreaking guide to the only physically justified way of operating electrodynamic loudspeakers - current-drive. The author claims the sound quality of virtually all speaker systems of the world has been severely impaired by the diverse spurious electromotive forces induced in the voice coil, that corrupt the flow of current; and what's dramatic - the evidence is plain and overwhelming! Written for all from the academic community to lay hobbyists. Besides new concepts for amplifier and speaker design and demonstrative projects, provides also novel ideas for modelling, filter design, measurements, and protection; and a helpful tutorial on analogue linear systems. For more details, visit www.current-drive.info.

From the back cover:

Is it indeed possible that all audio power amplifiers of the world operate and have operated since their inception - on an all wrong principle? Is it also possible that the sonic aberration caused by this gross technical mistake has substantially impaired our experience with loudspeaker-produced sound, with implications even on the musical evolution of our civilization?

According to laws of physics, electric current is that which in a speaker driver effects diaphragm acceleration, which in turn produces sound pressure. Yet all power amplifiers strive, even tooth and nail, to control the voltage at the loudspeaker terminals, which only indirectly affects the current flowing in the voice coil.

Current-controlling loudspeakers is nevertheless not an all-new concept. Some of the benefits it brings, like decreasing of harmonic distortion and expanding of frequency range, have been known at least by specialists. However, there prevails great ignorance about the many disastrous interference mechanisms that traditional voltage drive inevitably creates and that are fully or partially eliminable by correctly operating current-drive. Also, current-drive does not necessitate active speakers any more than voltage drive does, but amazing improvement in sound quality is achievable by simple means. Based on properties of linear systems and investigation, plenty of other flawed conceptions prevalent in the field of audio technology are also pointed out.

When writing this, virtually no full-range audio equipment operating on the current-principle has yet been seen on the market. One reason may be that controlling the resonance of the bass driver under current-drive has been considered difficult. To resolve this, new handy techniques and circuits are introduced, so that technical obstacles for the extensive utilization of the current-principle are cleared away. Also, it is shown that so-called electrical damping, that pertains to voltage drive, is actually a totally invalid argument for the choice of the driving method.

The book has been written out with easy-to-understand language for both professionals and interested laymen, so the novel amplifier and loudspeaker realization concepts are made available to all. An ordinary circuit simulator can be used also for predicting the acoustic response, without need for special software. In the appendices is provided valuable basic knowledge about analogue systems.


Retailers may order at 33% discount.

Feel free to link to my current-drive web site from any appropriate page.

Some ideas presented are subject of patent applications supported by the Foundation of Finnish Inventions.

Questions, feedback, and comments are welcome to my contact form.


Esa M.