Vintage Synth Repair

There's usually a wealth of information about things like this on my
www.imt.net/~sounddoctorin/synthtec page.  I think there might even be
a pointer to a block diagram for it I can't recall.  But anyway if you
are only listening to the brass/organ mix through the filter (the far
right volume knob in other words) then the VCF indeed comes before the
A-R envelop which is a final vca.  So if in other words, you have the
cutoff turned way down to squelch all signal, and an envelop amount
set so that you hear signal during up to the end of the attack
envelope time..but then you have decay set to zero then unless you
have sustain turned up enough to keep sounding coming out until you
release the keys, the envelope is already collapsed and thus the
'final decay' has no effect on the vcf PROVIDED you hold the keys down
beyond the extent of the attack envelope.  Hopefully that makes sense.
   -bob

--- In vintagesynthrepair@yahoogroups.com, "oxygeno1313"
<oxygeno1313@...> wrote:
>
> Hi all,
> 
> I have a Moog opus but i'm not sure if something are failing, the 
> test is :
> 
> BRASS section : VARIABLE position
> MIX to VCF : middle position
> 
> Articulator Mode 2
> Attack : 0
> Release : 7 - 10
> 
> VCF  Decay : 0 - 10
> Final Decay Swtich : ON
> 
> MIXER 
> 
> Chorus/Strings : OFF
> ORGAN DIRECT : OFF
> VCF (ORGAN, BRASS) : ON
> 
> This test is just to know if the Opus i have it's failing...
> 
> When you play some keys with high release (decay) at the articulator, 
> and the VCF DECAY at ZERO position there's no RELEASE !, but if i 
> turn up the VCF DECAY slider the RELEASE coming. My question is : 
> Both Decays are linked ? Seems that the VCF DECAY are the MASTER 
> DECAY.
> 
> The other problem is when i turn OFF the FINAL DECAY switch and start 
> playing notes and retrigger other notes, the sound of the first notes 
> still sound, so i hear a mess... I know that the ARTICULATOR MODE 2 
> it's for summing notes, but is this is correct ?
> 
> Any one can help me to confirm ?
> 
> Best Regards,
>