Doepfer

Hi Dieter

Should the A-183-1 passive attenuator cease passing a signal when its knob is fully counter-clockwise?

A-143-4 triangle out --> A-183-1 --> A-124 CV1

My A-183-1 attenuates the amount of LFO getting to the filter cut-off, but it never fully attenuates when the knob is fully counter-clockwise (i.e. "off"). Some LFO still gets through to the filter. Both channels on the A-183-1 exhibit the same behaviour.

Is that intentional?  Am I missing something in its usage?

Thanks.

> Hi Dieter
>
> Should the A-183-1 passive attenuator cease passing a signal when
> its knob is fully counter-clockwise?
>
> A-143-4 triangle out --> A-183-1 --> A-124 CV1
>
> My A-183-1 attenuates the amount of LFO getting to the filter
> cut-off, but it never fully attenuates when the knob is fully
> counter-clockwise (i.e. "off"). Some LFO still gets through to
> the filter. Both channels on the A-183-1 exhibit the same behaviour.
>
> Is that intentional?  Am I missing something in its usage?
>
> Thanks.

That's not the correct behaviour. The signal should be completely off if the
knob is fully ccw. One explanation would be the usage of patch cables
without GND because in this case the GND for the A-183-1 circuit is missing.
The A-183-1 is a passive module and does not pick-up the GND from the bus
board like other modules. It is essential that the GND is connected via the
patch cables.

Best wishes
Dieter Doepfer

> > Hi Dieter
> >
> > Should the A-183-1 passive attenuator cease passing a signal when
> > its knob is fully counter-clockwise?
> >
> > A-143-4 triangle out --> A-183-1 --> A-124 CV1
> >
> > My A-183-1 attenuates the amount of LFO getting to the filter
> > cut-off, but it never fully attenuates when the knob is fully
> > counter-clockwise (i.e. "off"). Some LFO still gets through to
> > the filter. Both channels on the A-183-1 exhibit the same behaviour.
> >
> > Is that intentional?  Am I missing something in its usage?
> >
> > Thanks.
> 
> That's not the correct behaviour. The signal should be completely off if the
> knob is fully ccw. One explanation would be the usage of patch cables
> without GND because in this case the GND for the A-183-1 circuit is missing.
> The A-183-1 is a passive module and does not pick-up the GND from the bus
> board like other modules. It is essential that the GND is connected via the
> patch cables.
> 
> Best wishes
> Dieter Doepfer

Hi again Dieter

Well, it seems I am mistaken. Today the A-183-1 behaves exactly like you said it should. I have no idea what happened a few days ago...faulty patch cable maybe? 

Anyway, I thought I would reply to the group in case anyone thought there was a problem with A-183's. Mine is fine.

Thanks.
Sean