Send a Trigger in an audio effect

Gfrom the B's icon

Hi Ppl,
I have a filter as an audio effect with an envelope on the cutoff. How can I trigger the envelope?

Thanks

Peter Ostry's icon

If it is in an [vst~] there is an output for changed parameters. Open the plugin, do manually what you want and look what leaves the particular output. This shows you what you have to send into the leftmost input for the desired action.

Gfrom the B's icon

Hi Peter, thanks for your comment.
not sure i got that, or maybe i was not clear.
I made an audio effect in max which contain a filter + an envelope that controls the cutoff.
so i added this device on a channel. - plugin is going to the input of the filter and plugout come from the output of the filter.
to make the envelope control the cutoff I need to send a trigger to the envelope....
did you suggest to add a vst~ to the patch ?

Peter Ostry's icon

I just guessed that you talk about a [vst~]
If not, forget my comment.
Unfortunately I do not understand what you mean.

nouserid's icon

You could add a little sequencer to trigger the envelope.

Max Patch
Copy patch and select New From Clipboard in Max.

Roman Thilenius's icon

if you already build an envelope, how you can not know how to trigger it?

Gfrom the B's icon

Hi ppl, Just came back after a while.
i was reverse engineering so i have a lot of knowledge holes.

I built an audio effect (just simple filter with envelope). what I did not find out is how to make the envelope start to work the moment the signal hit the filter.

Example for clarity: I synthsis an hand clap with ableton's opreator. but I wanted to shape it more with an ex filter. So I added after the synth the max filter that I made. So the synth sound goes trough an ex filter. all works fine just I dont find how to trigger the envelope filter the moment the clap goes in the filter.

nouserid's icon

One way to do it would be to put a midi effect like this before the instrument...

Max Patch
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...which would allow to you trigger your filter each time a midi note is played, like this.

Max Patch
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Gfrom the B's icon

Thanks Kyle, it seems to work :)
Off topic Q, when the envelope set on a really short attack times it creates (sometimes) a little click in the very beginning of the source. How can I avoid It?

broc's icon

The click may happen because send/receive introduces some variable delay relative to Live's audio buffer size. Try setting it as small as possible.

nouserid's icon

Happy to help :) I like to use [slide~] to smooth out clickyness...

Max Patch
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Gfrom the B's icon

When I added the slide~ i do not have a distorted random click anymore but still have the filter not tight 100%.

So in the beginning of the sound the filter is open for few ms and only then react to the envelope which set on a long attack. indeed seems to be latency, but not a real solution? ( appear also when the buffer is really low).

Also, did not sure I get from the "help" what the slide does. in case you have it in a short (or long) will be awesome.

Another issue that I recognize is that the envelope creates a really high tone (around 22K) for all the duration that the envelope set for.

nouserid's icon

Would you mind posting your patch so I could have a look?

Gfrom the B's icon

filter.maxpat
Max Patch
sure, thanks!

nouserid's icon

I've switched out a few objects to make the filter modulation at signal rate. It's always better to use signals for modulations like these just cuz they're more accurate. [slide~] basically just smooths out sharp changes in a signal. Let me know if this works.

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Gfrom the B's icon

I am learning here :) thank you!

Sometimes when I loop the sound and change/play with the parameters the filter stoped to react and I can't hear any sound trough the filter anymore. On the channel meter in ableton I see feedback but can not hear non. I guess it a really loud click that made it?
It seems like the only way to fix it is to restart ableton.

nouserid's icon

Sounds like the filter is blowing up. I think clipping the range on the filter modulation should fix that.

Max Patch
Copy patch and select New From Clipboard in Max.

Gfrom the B's icon

big thank you

nouserid's icon

Any time, GFROM THE B.