In the early 1980s I took to task one particular
manufacturer of audipile components, which were
claimed to cancel out the harmful nonlinear
effects of diodes, BJTs, capactors, switches,
even wire. At that time they offered (potted)
modules inside their equipment which affected the
'cancellation'. Who knows, maybe they even got a
patent. I wrote a letter to the company lashing
into their practice, as I was working on
broadcast audio gear at the time and was
astounded that anyone would buy this junk. The
president of the company wrote back a pathetic
letter explaining how I didn't understand their
technology and how they were absolutely certain
of their magical work.
Following is an excerpt from a 1998 Stereophile
magazine review of a particular Kinergetics power
amplifier, to explain what I am talking about:
>Kinergetics' signature design feature has long
>been their patented, so-called "KDP" circuit,
>designed to reduce what the company calls
>"hysteresis distortion." Kinergetics claims that
>all parts, including passive ones, exhibit
>nonlinearities that can compromise performance.
>Actually, all distortion is caused by
>nonlinearity of some sort or another, and though
>most engineers would put the blame on the active
>parts of a circuit (which are always nonlinear
>in some part of their operating range?the trick
>is to stay on the linear portion), passive
>devices are not entirely blameless, either. In
>typical amplifier designs, negative feedback is
>used to minimize the distortions that cannot be
>eliminated from the basic design (and no active
>parts, in particular, are completely free of
>nonlinear distortions).
>
>Kinergetics' explanation of how they solve this
>problem sounds suitably high-tech, but to me it
>sounds as if it operates in much the same way as
>local feedback. From the owner's manual: "We
>then create an electronic model of a capacitor's
>nonlinear distortion and put it into the
>negative input of the differential amp. The
>positive (real) and the negative (created)
>distortion now cancel each other?distortion
>removed!" (The term "hysteresis distortion" is
>unique to Kinergetics in this context. It is
>usually used to describe nonlinearities in
>ferrous materials such as transformer cores.
I am not certain they are still in business, but
certainly someone else has taken on their cause.
There is money to be made, and buyers to please.
73 and enjoy your tubes while you have 'em,
John
K5PRO
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