Dotcomformat

Ty, I believe some of your other questions also come down to nomenclature.  I 
think of the "FM input" as a cv input with attenuation.  If there is any 
difference at all, it must be a technical one.  You can use audio rate 
modulation of a cv input on any filter, regardless of the legending.  It sounds 
like you don't normally do this.  I recommend it.  I often use the STG filters 
without an audio input, in that jack at least.  Attenutated audio in the FM 
input with the resonance up a bit gets a much more interesting response in my 
opinion.  


I also use the FM input for an cv I want to attenuate.  If you look at the 
Yusynth board, I believe there are 3 CV in's on the SDF (it's been a while since 
I've looked, and I believe there may have been a revision along the way on the 
STG version.)  They all go to the same place.  Perhaps one has a different 
resistor or something, I don't know.  For my use, I don't distinguish between 
them aside for one having an attenuator. 


Caveat: I don't build these things, could be in the wrong, etc, but I don't 
believe so.

Cheers,
Brian





________________________________
From: ty hodson <yahoo123@infinitedensity.net>
To: dotcomformat@yahoogroups.com
Sent: Fri, June 3, 2011 7:16:22 PM
Subject: [dotcomformat] Questions re: STG Sea Devils and Post-Lawsuit filters

  


Hey all,
 
I just picked up Suit’s Sea Devils and Post-Lawsuit filters, and have been 
checking them out.  I came up with a few questions for Suit, but thought I’d 
post them here too since others may have some experience with these filters, in 
either STG’s or their original incarnations, and can hopefully clear up my 
cloudiness…
 
+ Both filters
  -- Regeneration... Is this the same as Resonance?  If so, any significance to 
the different name?  If not, what does Regeneration mean?
  -- Two Control Inputs... Do they control two different things?  Or are they 
combined?  Do they only affect the frequency cutoff?
  -- FM Input... I don't think I've ever encountered a filter with an "onboard" 
FM Input... What advantages are there for having this input on the filter versus 
performing the FM before the filter is added to the signal chain?
 
+ Sea Devils - http://stgsoundlabs.com/products/sea_devils_filter_mu.htm
  -- While A/B'ing the two filters with the same oscillator (triangle wave) 
source, I noticed that the output of the Sea Devils filter was substantially 
lower than the Post-Lawsuit filter.  Is that expected?  I don't mean to suggest 
that they -should- have the same perceived volume, but I was just curious.
 
+ Post-Lawsuit - 
http://stgsoundlabs.com/products/post_lawsuit_lowpass_filter_mu.htm
  -- Two Audio Inputs... How does a second audio input differ from an FM Input?
  -- No Regeneration Input... Was that a design decision based on the additional 
Audio Input that had to be accommodated?
 
After writing up these questions, I checked out Yves Usson’s site for more 
insight, since STG’s filters are based on Yusynth’s work.  But Yves doesn’t go 
into a lot of blow-by-blow detail on the jacks and pots for each module. 

 
http://yusynth.net/Modular/EN/EMSVCF/index.html
 
http://yusynth.net/Modular/EN/ARPVCF/index.html
 
It does appear that STG picked and chose among available features in order to 
create his 1U versions.  I’d love to know more about why he chose the features 
he did, and opted to not use others.  And in the case of the FM input, I don’t 
see such a thing on either of the Yusynth versions… So where did this come from, 
and why is it on these filters??  : )
 
Thanks!
ty
 
 
_______________
http://sublevel9.net