This is great! One thing though, I had to modify the code to run, the random:i in the init functions at the start produced the following error:

syntax error, opcode 'init' for expression with arg types i returns out-args != 1, line 36

from file c:\Users\rory\sourcecode\cabbage3-recipes\samples\Feedback.csd (1)

syntax error, opcode 'init' for expression with arg types i returns out-args != 1, line 37

from file c:\Users\rory\sourcecode\cabbage3-recipes\samples\Feedback.csd (1)

I'm using Csound 7.0 on Windows. I had to change it to:

    fb1:a = init:a(random:i(0.5, 1))

    fb2:a = init:a(random:i(0.5, 1))

It makes a nice synth, although the initial delay when it starts make it less useable in that way. But the timbres are very nice. It's fun to stack the carrier wave with harmonics too. 

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thanks for sharing luis --- very interesting sound and quite instructive 
code.

i had the same issue as rory with the code, but the solution with init:a 
does not lead to the sounding result which i have with
   fb1:a init random:i(0.5, 1)
   fb2:a init random:i(0.5, 1)

i changed the carrier frequency from 200 to randomi:k(100,300,1/10,3) 
and liked the result.  it would be nice to create a system where certain 
parameters change depending on situations.  martin neukom did this in a 
quite simple csound file in his Signale Systeme Klangsynthese book 
twenty years ago, with crazy results.

On 11/11/2026 20:28, Rory Walsh wrote:
> I think certain things were permitted in the beta builds that have since 
> been locked down, otherwise this could be flagged as breaking backward 
> compatibility?
> 
> On Wed, 11 Nov 2026 at 16:07, luis antunes pena <00000fd5d0d20dbf-dmarc- 
> request@listserv.heanet.ie  request@listserv.heanet.ie>> wrote:
> 
>     __
>     Giovanni and Rory,
> 
>     thanks for testing!
> 
>     Rory: this may be due to the fact that I am not using the very last
>     csound 7 version? I noticed now that I haven't updated it yet to the
>     newest Trapani release. I have the --Csound version 7.0 (double
>     samples) Feb  7 2026
> 
>     So there is a difference between fb1:a = init(random:i(0.5, 1)) and
>     fb1:a = init:a(random:i(0.5, 1)) The first works in my csound 7 from
>     February. So the init needs to produce an audio signal although the
>     random:i is an i-signal.
> 
> 
> 
>     On 11/11/2026 16:38, Rory Walsh wrote:
>>     This is great! One thing though, I had to modify the code to run,
>>     the random:i in the init functions at the start produced the
>>     following error:
>>
>>     syntax error, opcode 'init' for expression with arg types i
>>     returns out-args != 1, line 36
>>     from file c:\Users\rory\sourcecode\cabbage3-
>>     recipes\samples\Feedback.csd (1)
>>     syntax error, opcode 'init' for expression with arg types i
>>     returns out-args != 1, line 37
>>     from file c:\Users\rory\sourcecode\cabbage3-
>>     recipes\samples\Feedback.csd (1)
>>
>>     I'm using Csound 7.0 on Windows. I had to change it to:
>>
>>         fb1:a = init:a(random:i(0.5, 1))
>>         fb2:a = init:a(random:i(0.5, 1))
>>
>>     It makes a nice synth, although the initial delay when it starts
>>     make it less useable in that way. But the timbres are very nice.
>>     It's fun to stack the carrier wave with harmonics too.
>>     Csound mailing list Csound@listserv.heanet.ie
>>      https://listserv.heanet.ie/cgi-
>>     bin/wa?A0=CSOUND 
>>     Send bugs reports to https://github.com/csound/csound/issues
>>      Discussions of bugs and
>>     features can be posted here 
>     ____ Csound mailing list Csound@listserv.heanet.ie
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>     bin/wa?A0=CSOUND 
>     Send bugs reports to https://github.com/csound/csound/issues
>      Discussions of bugs and
>     features can be posted here 
> 
> Csound mailing list Csound@listserv.heanet.ie 
>  https://listserv.heanet.ie/cgi-bin/ 
> wa?A0=CSOUND  Send bugs 
> reports to https://github.com/csound/csound/issues  csound/csound/issues> Discussions of bugs and features can be posted here

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