Wiardgroup

I received my Borg Filter about a week ago. Needless to say its 
amazing! One thing puzzles me though.... How do I feed an 
ADSR to it? None of the jacks are obviously labeled for this 
function. Just for the record, I'm using MOTM 800 EG's.
                
                Thanks,
                John

>     I received my Borg Filter about a week ago. Needless to say its
>amazing! One thing puzzles me though.... How do I feed an
>ADSR to it? None of the jacks are obviously labeled for this
>function. Just for the record, I'm using MOTM 800 EG's.

The Mod inputs, although the 5v motm envelopes won't open the 
frequency completely as the Wiard uses a 10v standard.

--- In wiardgroup@y..., liquidcolor@e... wrote:
> >     I received my Borg Filter about a week ago. Needless to 
say its
> >amazing! One thing puzzles me though.... How do I feed an
> >ADSR to it? None of the jacks are obviously labeled for this
> >function. Just for the record, I'm using MOTM 800 EG's.
> 
OK, I was not aware that the MOTM ADSRs had a 5 volt output. In 
that case, connect to both KEY FOLlow and MODulation inputs. 
This will allow the 5 volt envelope to sweep over the full range of 
the filter.

This is true for any set of inputs. The input summers form the 
agebraic sum of the inputs (in other words they add up positive 
and negative voltages). So the effect of connecting to more than 
one input is to multiply by the number of connected inputs.

i + i = 2 x i
i + i + i = 3 x i

As additional background, a synthesizer with +/- 15 volt power 
supplies has an internal voltage range of 30 volts minus the 
voltage limit of the op-amp outputs. In the case of TL074s, they 
limit at 13.5 volts. So the largest signal that can exist internally is 
27 volts peak to peak.

Now if the oscilators produce 10 volts peak to peak, summing 
two oscillators produces a 20 volt peak to peak signal, and 
summing 3 oscillators produces a 30 volt peak to peak signal, 
which can not exist internally. For this reason, the oscillators 
actually produce an 8 volt peak to peak signal, so three can be 
summed together to produce a 24 volt peak to peak signal, 
without clipping.

The VCAs on the oscillators have a gain of 1.25 so if an 8 volt 
peak to peak signal is run through them, it will be amplified to 10 
volts peak to peak.

The Wiard is designed to minimize distortion, unless you want it. 
If you route the sawtooth signal through the VCA set to 
maximum, and then route the signal to IN1, IN2 and IN3 on the 
Omni-Filter, it will be clipped and distorted. Or any waveform 
routed to all 4 inputs on the Omni-Filter will be clipped and 
distorted by the 4 x gain at the input.

i + i + i + i = 4 x i

Of course this applies to all modulars and not just the Wiard.

> I'm using MOTM 800 EG's.
> > 
> OK, I was not aware that the MOTM ADSRs had a 5 volt output. 

Can someone please supply me with a copy of the MOTM 800 
schematic?

It should be very simple to adjust them for simultaneous 5 volt 
and 10 volt outputs. The Vpeak reference for the flip-flop reset 
may be set with a single resistor. Then the 5 volt output can be 
derived by a passive divider. The best of both worlds.

Once again, this is not a slight at Paul, he has excellent reasons 
for doing things the way he does. This would just make it easier 
for those with mixed module systems.

Thank you,

Grant Richter

it's basically the same thing as Tom Henry's ADSR from Polyphony.

R.
----- Original Message -----

From: grantrichter2001 <grantrichter2001@yahoo.com>
To: <wiardgroup@yahoogroups.com>
Sent: Thursday, June 27, 2002 11:18 AM
Subject: [wiardgroup] Re: Borg + ADSR


> > I'm using MOTM 800 EG's.
> > >
> > OK, I was not aware that the MOTM ADSRs had a 5 volt output.
>
> Can someone please supply me with a copy of the MOTM 800
> schematic?
>
> It should be very simple to adjust them for simultaneous 5 volt
> and 10 volt outputs. The Vpeak reference for the flip-flop reset
> may be set with a single resistor. Then the 5 volt output can be
> derived by a passive divider. The best of both worlds.
>
> Once again, this is not a slight at Paul, he has excellent reasons
> for doing things the way he does. This would just make it easier
> for those with mixed module systems.
>
> Thank you,
>
> Grant Richter
>
>
>
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>
>

--- In wiardgroup@y..., "grantrichter2001" <grantrichter2001@y...> 
wrote:
> > I'm using MOTM 800 EG's.
> > > 
> > OK, I was not aware that the MOTM ADSRs had a 5 volt 
output. 

OK, Paul Schrieber has been kind enough to inform me that both 
outputs can be converted to +10 volt peak by lifting either side of 
R14.

The signal exists at a +10 volt peak at pin 1 of U3. You could also 
connect a 1K ohm 1/4 watt 5% resistor in series with Pin 1 and 
the tip of a 3.5mm jack and have both +10 and +/- 5 volt 
envelopes available simultaneously.

This would be useful when interfacing to ARP, Wiard and Blacet 
synthesizers.

I would like to thank Paul for being so generous as to provide 
this information.

If you want a +10 V max. output, remove resistor R14
(2K). You can just clip it off the top side of the pc
board.

Paul S.


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--- In wiardgroup@y..., "grantrichter2001" <grantrichter2001@y...> 
wrote:

> The VCAs on the oscillators have a gain of 1.25 so if an 8 volt 
> peak to peak signal is run through them, it will be amplified to 10 
> volts peak to peak.

Does this mean that the nearby lag processor needs a 12.5 volt 
voltage to perform attenuation over the VCA's full range; or is the 
VCA's CV input amplified by 1.25 as well?

S. Kuehnl

--- In wiardgroup@y..., "skuehnl" <skuehnl@y...> wrote:
> --- In wiardgroup@y..., "grantrichter2001" <grantrichter2001@y...> 
> wrote:
> 
> > The VCAs on the oscillators have a gain of 1.25 so if an 8 volt 
> > peak to peak signal is run through them, it will be amplified to 
10 
> > volts peak to peak.
> 
> Does this mean that the nearby lag processor needs a 12.5 volt 
> voltage to perform attenuation over the VCA's full range; or is the 
> VCA's CV input amplified by 1.25 as well?
> 
> S. Kuehnl

Sorry for that; the question is silly because I was thinking of a 
differently working type of VCA. Forget it.