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New CGS module--Slope Detector

New CGS module--Slope Detector

2005-12-31 by rdrake

Not sure when this became available, or if it was announced here, but I just noticed it:

http://www.cgs.synth.net/modules/cgs62_sd.html

"The slope detector is an event-driven gate/trigger generating device. It monitors a control voltage, and responds according to what that voltage is doing. If the voltage is rising, the slope detector gives a "gate" output (approx. 5V) on its "rising" output. Likewise, if the voltage is falling, the slope detector gives an output on its "falling" output. The duration of this gate signal depends on the incoming CV and the setting of the sensitivity pot. When the CV is remaining constant, the "steady" output activates."

Thanks as always, Ken!

bbob

Re: New CGS module--Slope Detector

2005-12-31 by Richard Brewster

Ah! Nice little module. The inverse of the "steady" output means the
signal is moving. I like it. I want something like this to detect when
a new voltage appears on a sample and hold, or when my Blacet Miniwave
puts out a new value in quantizer mode. Or when the CGS Infinite Melody
puts out a new value. I wonder if it would work for this. The period
of change would be very short. You think this slope detector would work
here? It would need to output a short pulse when it detects that the
input changed to a new level.

-Richard Brewster

rdrake wrote:
Show quoted textHide quoted text
>Not sure when this became available, or if it was announced here, but I just noticed it:
>
>http://www.cgs.synth.net/modules/cgs62_sd.html
>
>"The slope detector is an event-driven gate/trigger generating device. It monitors a control voltage, and responds according to what that voltage is doing. If the voltage is rising, the slope detector gives a "gate" output (approx. 5V) on its "rising" output. Likewise, if the voltage is falling, the slope detector gives an output on its "falling" output. The duration of this gate signal depends on the incoming CV and the setting of the sensitivity pot. When the CV is remaining constant, the "steady" output activates."
>
>Thanks as always, Ken!
>
>bbob
>
>
>

Re: New CGS module--Slope Detector

2005-12-31 by Edward r Jones

That is going straight to the poolroom!

What a brilliant idea! Useful for synthing, but, for general purpose electronics fault finding, too.
Use a ribbon controller (or analog joystick), and have up and down trigger different drum sounds! I've got the Big Kevs over stuff this circuit can do.

However, I'm going to have to build the few boards I purchased recently first, so as to assuade my reputation of being a man who doesn't always finish things.

I joined the group a while ago, and have been a sleeper againt for a few days, and I thought I'd pop my head up and say G'day to everyone.

Keep up the good work guy, and Ken most of all!

-edward

rdrake <rdrake@...> wrote: Not sure when this became available, or if it was announced here, but I just noticed it:

http://www.cgs.synth.net/modules/cgs62_sd.html

"The slope detector is an event-driven gate/trigger generating device. It monitors a control voltage, and responds according to what that voltage is doing. If the voltage is rising, the slope detector gives a "gate" output (approx. 5V) on its "rising" output. Likewise, if the voltage is falling, the slope detector gives an output on its "falling" output. The duration of this gate signal depends on the incoming CV and the setting of the sensitivity pot. When the CV is remaining constant, the "steady" output activates."

Thanks as always, Ken!

bbob



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Re: New CGS module--Slope Detector

2005-12-31 by sasami@hotkey.net.au

It will detect these changes without any problems. And it would only output
a short pulse. That is because it is detecting a very steep and quick slope
(i.e. a vertical edge).
Show quoted textHide quoted text
>Ah! Nice little module. The inverse of the "steady" output means the
>signal is moving. I like it. I want something like this to detect when
>a new voltage appears on a sample and hold, or when my Blacet Miniwave
>puts out a new value in quantizer mode. Or when the CGS Infinite Melody
>puts out a new value. I wonder if it would work for this. The period
>of change would be very short. You think this slope detector would work
>here? It would need to output a short pulse when it detects that the
>input changed to a new level.
>
>-Richard Brewster
>
>rdrake wrote:
>
>>Not sure when this became available, or if it was announced here, but I
just noticed it:
>>
>>http://www.cgs.synth.net/modules/cgs62_sd.html
>>
>>"The slope detector is an event-driven gate/trigger generating device. It
monitors a control voltage, and responds according to what that voltage is
doing. If the voltage is rising, the slope detector gives a "gate" output
(approx. 5V) on its "rising" output. Likewise, if the voltage is falling,
the slope detector gives an output on its "falling" output. The duration of
this gate signal depends on the incoming CV and the setting of the
sensitivity pot. When the CV is remaining constant, the "steady" output
activates."
>>
>>Thanks as always, Ken!
>>
>>bbob
>>
>>
>>
>
>
>
>
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: New CGS module--Slope Detector

2005-12-31 by Gerald Stevens

Seems like this module gets me half-way towards the goal of chain-able ADSR
modules.
I was thinking about putting together an ADSR that would trigger at a
set-point on a falling
edge. It would also have gain, and offset controls, and would have an input
/ output that
would add the previous ADSR in the chain, and send the result to the next
ADSR. This way,
you could create as complicated an envelope as you wanted, given enough
modules and patience.

Nice thing about Ken's module with regards to this application is that you
could trigger on rising
edges, and possibly on sustained portions too?

-gerald


[Non-text portions of this message have been removed]

Re: New CGS module--Slope Detector

2006-01-01 by peng3002

--- In cgs_synth@yahoogroups.com, "rdrake" <rdrake@d...> wrote:
Show quoted textHide quoted text
>
> Not sure when this became available, or if it was announced here,
but I just noticed it:
>
> http://www.cgs.synth.net/modules/cgs62_sd.html
>
I just built this today and I've only experimented with it a little
bit. Some observations:

Input = ADSR (attack up, decay up, sustain 0, release 0)

During the attack portion the rising LED/output is lit/high.
During the decay portion the falling LED/output is lit/high.
When the envelope transistions from attack to decay the steady output
goes high briefly. At the end of the decay stage the steady output
FADES in and the steady output goes high and remains high.

I have two questions:
Is the steady output supposed to go high briefly at the point the CV
changes directions? Adjusting the pot extends this blip to be longer
or shorter but doesn't eliminate it entirely.

Is the steady output supposed to FADE in as mine does? It surprised
me because I thought it would be either full on or full off.

Someone please tell me if this isn't working right. Breadboards are
never bulletproof.

Ken. this is a nice addition to the line-up. I'm very impressed with
the simplicity to usefullness factor. The extra buffering for the LED
supplies is nice.

Thanks,
peng

Re: New CGS module--Slope Detector

2006-01-01 by sasami@hotkey.net.au

>
>I have two questions:
>Is the steady output supposed to go high briefly at the point the CV
>changes directions? Adjusting the pot extends this blip to be longer
>or shorter but doesn't eliminate it entirely.

The blip is there because there is a tiny voltage gap between rising
detection and falling detection. It could only be eliminated by adding a
short delay to the steady output. (add a small cap across the 10k pullup for
the steady driver pnp?)

>Is the steady output supposed to FADE in as mine does? It surprised
>me because I thought it would be either full on or full off.

No. We are talking comparators here - either on or off. Any fading has to be
an error you maed building it.

Ken

_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

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