Hi Peter,
> There is a way to self oscillate a Doepfer ADSR if you have a
tirgger modifier
> module as well. I do it all the time:
>
> Positive out of ADSR into Trigger Mod.
>
> Pulse out of Modifer into Retrigger in of ADSR
>
> Put a cotat high voltage oce ito the gate iput of the ADSR ad
remove it before
> the cycle eds.
I don't have an A-165, but I assume that when you do this the re-
trigger level is at the mercy of whatever is inside the 165 which
decides when it has seen a 'trigger'
> As far as a mod to self osc, this would be easy:
>
> Output of the ADSR through a comparitor, going into the - in. The
comp. +
> reference set just a tad above ground (really really close to
ground). Output of
> that through a switch to turn it off and on, output of that to a
diode to the gate
> or retrigger input.
Mmm, I can see a philosophical debate coming on about what a cycling
ADSR really _is_. The 'mod' I've been playing with (I'm still
pondering over it, because I keep having trouble deciding what is
sensible and what is not, and this kind of comment reinforces this
fact...) is almost exactly what you describe _except_ that the
reference level will be the sustain level. Thus whereas with your way
the ADSR swings through its full output range, my way it will only
swing between the max output level and the sustain level, which
perhaps is more flexible ( ), i.e. it will be as your way when the
sustain level is set very low. I've certainly had some great 'echo'
like effects with it.
> This will give you an AR LFO as well. It's a pain to self cycle an
ADSR,
> because it needs sustained gate input to complete the last two
phases.
Not quite sure what you mean here - what I'm thinking of will only
cycle _as long as_ the gate remains there. Since it re-cycles each
time the sustain level is hit, there is no sustain phase per se, and
when the gate closes, you get the release phase as normal.
My idea is actually working out a deal more simple than I thought,
and in its simplest form will only require cutting 1 track, adding 1
strap, and snipping through 1 resistor. I'm trying to organise a
friend who has a digital camera so that when I do it I can post some
pikkies. (There are also several pairs of diodes in the circuit whose
purpose I haven't fully grasped yet, and I don't want to rush into it
and overlook something....)
You've also made me want to check what happens if I switch it in and
out via an A-150 _whilst the gate stays open_ to see if it restarts
cycling when I switch it back in.
Tim