Making synth nodes survive Ctl-period

Questions
1

Hi list,

albeit this might have been discussed already, I am trying to .add a
synth def to my server and making that that synth survive ctl-period.

Following this helpful startpage.com search result
https://www.reddit.com/r/supercollider/comments/virv1c/synth_surviving_cmdperiod/
I am able to add the Synth to the ServerTree and the synth node is
re-created upon Ctl-period like this:

(
~init = { Synth(\default) };
ServerTree.add(~init);
Synth(\default);
)

In this code I have to start the synth once.

Now, I am running into the issue that this synth node is
created a second time whenever I (have to) re-evaluate that code as part
of a bigger initialization block.

I wonder if there is an even better way to achieve the permanent node
but avoiding the double-creation?

Thanks for all ideas!
best, Peter

3

You have to be careful if you call such a block multiple times if you redefine ~init and then add it again you will end up with multiple copies of the function. You need to define ~init outside the block, or check to see if it exists before defining like ~init = ~init ? {your function}

you’ll also want to store your synth somewhere and check if it exists before recreating the synth like:

~synth.isNil.if {~synth = Synth(\default) }

beyond that you might want to register your synth Synth(\default).register so that you can check if its running with ~synth.isRunning so that you can recreate it if it has been stopped.

For persistent nodes another way is to write a Class so that stuff is added to the ServerTree during class tree initialization - you can check out one of the Quarks that does this like SafetyLimiter for example.

4

Thanks for the useful tips and examples Michael!

Which Quark is the SafetyLimiter in? I couldn’t find it by browsing the
list of Quarks in the IDE and it seems there is no search function for
classes provided by Quarks(?).

best, P

5

To search Quarks check out Baryon - here’s another quark that may be useful to you Baryon _ PersistentMainFX

And here is StageLimiter (sorry I had gotten the name wrong plus it’s part of the Batlib quark! ) BatLib/StageLimiter.sc at master · supercollider-quarks/BatLib · GitHub

6

There’s also SafetyNet. That seems more robust to me, but in practice I’ve never had any issues doing it the way that Batlib does it.

7

Also, if you’re doing this because you need a limiter at the end of the chain, then Nathan Ho wrote a good one.

You could use it with SafetyNet.

If you want a mixer channel at the end, then PersistentMainFx might be useful - but I’m less familiar with that one.

8

This is Nathan’s extension:
Safety Limiter