Errant triggers are caused by contact bounce, which is due to two
things. First is the design of the weighted action itself. While
well-balanced, each key ultimately strikes a small rubber pad,which is
in fact the force-sensing resistor array's cover delivering that
immaculate aftertouch. This results in a small bounce of the far end of
the key's 'rib' which is where the actual switch(es) are. At times this
bounce can cause a retriggering of envelopes. Second is the age of the
switches. Their design is going to last a hundred years, but contacts
do wear down, and they are already 30 years old. A little less contact
facing means a slightly wider contact gap, and a wider gap means the
above mentioned bounce has a greater chance of retriggering a note
envelope/rotation.
I tinkered with a corrective circuit, but am unsure if the correction
is 'better' (essentially a one-shot with a time of 50ms or so for each
trigger switch--16 in all).
Scott
/∗∗/
JH. wrote:
>> I noticed some of your keys double-trigger the notes like mine does.
>> How can we fix that?
>>
>
> I've no idea.
> It doesn't bother me much, though. As long as I don't get _wrong_ notes.
> But I sometimes get them; I suspect when a bouncing key triggers the first voice not long enough to fully charge the capacitor of the S&H?
>
> JH.
>