There is a problem with your code that may be related to your issue.

You are not running a filterbank, you are running the same two filters over and over again, which is a different thing. Since the filters are not pure functions, you can't put them in a loop and expect them to work as if each iteration was independent from the previous.

If you want a filterbank, you have 3 options:

1) Use separate filters, no loops.
2) Use a filterbank opcode.
3) Use a recursive UDO.

best

Prof. Victor Lazzarini
Maynooth University
Ireland

> On 4 Apr 2023, at 17:58, Massimiliano Tonelli  wrote:
> *Warning*
> 
> This email originated from outside of Maynooth University's Mail System. Do not reply, click links or open attachments unless you recognise the sender and know the content is safe.
> 
> Thank you so much for your reply! I tried both (k-rate index and while loop), but still no success.
> 
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Ah, I missed that and was focused on the k-rate loop. Victor's right on here.

On Tue, Apr 4, 2023 at 1:54 PM Victor Lazzarini  wrote:
>
> There is a problem with your code that may be related to your issue.
>
> You are not running a filterbank, you are running the same two filters over and over again, which is a different thing. Since the filters are not pure functions, you can't put them in a loop and expect them to work as if each iteration was independent from the previous.
>
> If you want a filterbank, you have 3 options:
>
> 1) Use separate filters, no loops.
> 2) Use a filterbank opcode.
> 3) Use a recursive UDO.
>
> best
>
> Prof. Victor Lazzarini
> Maynooth University
> Ireland
>
> > On 4 Apr 2023, at 17:58, Massimiliano Tonelli  wrote:
> > *Warning*
> >
> > This email originated from outside of Maynooth University's Mail System. Do not reply, click links or open attachments unless you recognise the sender and know the content is safe.
> >
> > Thank you so much for your reply! I tried both (k-rate index and while loop), but still no success.
> >
> > Csound mailing list
> > Csound@listserv.heanet.ie
> > https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Flistserv.heanet.ie%2Fcgi-bin%2Fwa%3FA0%3DCSOUND&data=05%7C01%7CVictor.Lazzarini%40mu.ie%7Cdd0e83d713204ea050a708db352dd011%7C1454f5ccbb354685bbd98621fd8055c9%7C0%7C0%7C638162243108936516%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=ig8Sm6A8Evr7kVWJPgHXauHxPsXUZcvuvMb%2Fd4wvOQs%3D&reserved=0
> > Send bugs reports to
> >        https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fcsound%2Fcsound%2Fissues&data=05%7C01%7CVictor.Lazzarini%40mu.ie%7Cdd0e83d713204ea050a708db352dd011%7C1454f5ccbb354685bbd98621fd8055c9%7C0%7C0%7C638162243108936516%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=Qf8mdLt7aAKKVwgADkYnuAO33DZkYqHQ9SpAkiW1is4%3D&reserved=0
> > Discussions of bugs and features can be posted here
>
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> Send bugs reports to
>         https://github.com/csound/csound/issues
> Discussions of bugs and features can be posted here

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