At the weekend I began to finish the development of the BBD module
(additional CV out, polarizer for CV2 ...) I found that we overlooked a very
important feature: it is a big difference if the original signal is mixed
with the delayed signal (not inverted) or the inverted delayed signal. The
resulting sounds are quite different. The reason is easy to understand if
one uses a VCO sawtooth as audio input signal for the BBD module. Adding the
delayed sawtooth to the original sawtooth leads to kind of a double
sawtooth. Adding the inverted delayed sawtooth to the original sawtooth
(50:50 level) generates a rectangle !

As we have now two polarity switches available (one for polarity of the
feedback and another for the polarity of the delayed signal) we will also
replace the planned polarizer for CV2 by a normal attenuator and a polarity
switch and add this type of switch for CV1 (i.e. function of CV1
positive/off/negative). I think that this leads to more clearness as each of
the four switches has the same function (negative/off/positive). And the
three-position on-off-on switches are not much more expensive than the
two-position on-on types. The middle position allows to turn off the
function in question (i.e. CV1 control, CV2 control, feedback, mixing of the
delayed signal to the original signal).

I will update the BBD info page probably tomorrow (including the new front
panel and a graph that shows the effect of adding the normal/inverted BBD
signal to the original).

I ask for your understanding that this will cause a small delay in the
delivery deadline (doen't that fit to a "delay module" ... :-) but I think
that these additional features are essential for the BBD module. I hope the
first BBD modules will be available April 2006.

Best wishes
Dieter Doepfer