[PD] Trigger/Gate

Roman Haefeli reduzent at gmail.com
Fri May 25 19:42:21 CEST 2018

Hi Rainer

On Fri, 2018-05-25 at 18:55 +0200, Rabbit ́s . wrote:
> Hi there,
> I´m doing a sequencer in pd for my modular rig starting with a
> trigger/gate abstraction that should bang the analog envelopes &
> friends. A very simple approach starting as trigger and ends up in
> variable gatelenghts - see patch attached.
> If I bang it manually there is no problem. If I bang it with a metro,
> the gate starts to wiggle a bit in lenght.
> Hmmm, guess there is a sync problem with free running metro and
> dac~???

Not really. The [line~ ] object starts (and ends, I guess) ramps only
on block boundaries, while the [metro] sends bangs with exact time
periods, and so does [delay]. It happens that the bang arrives
sometimes at the start of the block, sometimes at the end, the same
with the bang from [delay]. So the number of full blocks that fit
between the metro bang and the delay bang varies by one block. 

The reason why you don't see that jumping when manually triggering the
gate is that GUI interventions are quantized to blocks (or even more

If you want to have a (sub)sample-precise envelope, you need to use
[vline~] which is able to generate ramps starting and ending at any
time, even in between samples. Simply replace [line~] with [vline~] in
your patch. You will notice that not the length of the envelope is
wiggling now, but the position. This is due to [tabwrite~] being able
to start writing to a table only at block boundaries, too.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: This is a digitally signed message part
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20180525/5d8c1d3f/attachment.sig>

More information about the Pd-list mailing list