[Elecraft] KDSP is done

[Lyle Johnson]

Hello Kevin!

> Can you please clarify your statements about the KDSP
> and it causing distortion in the audio....
> I have used a JPS Communications NIR-10 DSP unit for
> several years. It was an expensive purchase at one of
> my trips to Dayton... I would expect the KDSP2 would
> behave in a similar fashion.

Please read the paper I wrote and which is on the Elecraft website
(http://www.elecraft.com/KDSP2/kdsp2design.pdf) about the design of the
KDSP2.  It explains the design decisions for the algorithms used.

The JPS unit you mention uses spectral subtraction for its noise reduction;
the KDSP2 uses least-mean-squares.  Each has its strengths and weaknesses;
both add audio artifacts.  The artifacts sound different between the two
methods.

The KDSP2 allows you to vary all three parameters which affect the noise
reduction: filter length, coefficient attack, and coefficient decay.  This
unparalleled flexibility allows you to tailor the amount and type of noise
reduction to suit your personal audio tastes and preferences under various
band conditions.

73,

Lyle KK7P