Wiardgroup

Great News!
When do you expect the 'first' Bug's to ship?

Have a quick question on my 'favorite' Wiard filter sound:

When I set the OMNI filter somewhere 'in between' LP and BP I get a
*wonderful* very musical distortion....what is happening electronically
during this setting?

r

Can't get my "the Filter" to buzz between modes.
Based on the block diagram, I'd hazard a guess that a low sideband 
of the hi-freq dithering clock is modulating the audio's amplitude 
(AM)
whadda you think? your supreme wogglehood?
-doc 


--- In wiardgroup@y..., "r" <robertkleckner@e...> wrote:
> 
> Great News!
> When do you expect the 'first' Bug's to ship?
> 
> Have a quick question on my 'favorite' Wiard filter sound:
> 
> When I set the OMNI filter somewhere 'in between' LP and BP I get a
> *wonderful* very musical distortion....what is happening 
electronically

> during this setting?
> 
> r

> When do you expect the 'first' Bug's to ship?

As soon as humanly possible!

> 
> Have a quick question on my 'favorite' Wiard filter sound:
> 
> When I set the OMNI filter somewhere 'in between' LP and BP I 
get a
> *wonderful* very musical distortion....what is happening 
electronically
> during this setting?

The Omni Filter takes 4 filter sections and rewires them into the 
4 common modes using solid state switches. The solid state 
switches will switch VERY fast, so you can switch them at an 
ultrasonic rate. This is the equivalent of making them behave like 
VCAs. In the between settings (more than one mode light on) 
they are crossfading between filter modes. This was done in 
order to fit the 20 VCAs needed into the enclosure.

The switching frequency is 44.1 Khz. To avoid aliasing 
(ultrasonic ring modulation) there are 24 dB/Octave 20 Khz guard 
filters on the input and output. At least in theory, the entire system 
should be linear and will not produce distortion unless the Q 
control is up. Q is actually regeneration, or taking the output and 
mixing it in with the input (Regeneration would not fit on the 
panel). Since you are adding the output back into the input, this 
produces gain which can lead to distortion (clipping).

I think it has to do with gain produced by the Q control. The 
regeneration produces gain which can lead to clipping.

There is sort of a philisophical note about distortion. Any change 
to the input waveform can be considered distortion. So a filter 
produces distortion by changing the waveform. For obscure 
mathematical reasons, this is not called distortion. Typically in 
engineering, distortion is refered to as any effect produced by 
"non-linearity" which is when the output does not relate precisely 
to the input using the equation x = by+a (which is the classic 
"slope offset" formula from algebra).

Non-linear distortion is used to "bend" the straight line sawtooth 
wave in the Waveform City into all those other waveforms. The 
waveshaper can process any signal, and running the output of 
the Omni Filter through the waveshaper is how you get those 
TB-303 "squonk" noises you hear on the Nike commercials.

--- In wiardgroup@y..., drmabuce@y... wrote:
> Can't get my "the Filter" to buzz between modes.
> Based on the block diagram, I'd hazard a guess that a low 
sideband 
> of the hi-freq dithering clock is modulating the audio's 
amplitude 

> (AM)
> whadda you think? your supreme wogglehood?
> -doc 
>