[PD] can [bp~] be obtained with biquad coefficients?

[Alexandre Torres Porres]

"Those bypass fiters"

oops, meant "Those bandpass filters"


2014-04-09 9:59 GMT-03:00 Alexandre Torres Porres <porres at gmail.com>:

> Hi, that is the way I'm pointing to. I know of those but it's a bit more
> complicated than that. Those bypass fiters have zero values of -1 and 1,
> while [bp~] has only pole values. So my question is if I can achieve [bp~]
> by only turning the zero values of -1 and 1 to 0. I actually tried it and
> it didn't seem to do the trick.
>
> Maybe I'm doing something wrong. I don't know. It'd solve my issue if I
> could have [bp~] as biquad coefficients. But if not, I'd need some
> guidelines on how to plot the frequency response in the same way as
> [filterview] or [mmb.filterplot] plot the biquad coefficients.
>
> Cheers
>
>
> 2014-04-09 8:30 GMT-03:00 Colet Patrice <colet.patrice at free.fr>:
>
>  Le 09/04/2014 01:45, Alexandre Torres Porres a écrit :
>>
>> Hi there. I'm trying to find a way to plot the frequency response
>> of [bp~].
>>
>>
>> Hello, I don't know if it helps, in ggee there are filter objects that
>> are applying formula for biquad coefficients, it's easy to use those
>> formula in expr and apply them to biquad object in vanilla.
>>
>>  I know of patches that can plot from biquad coefficients, so it'd be
>> great if I could get biquad coefficients from an input of frequency and Q.
>>
>>  I see [bp~] is a 2 pole filter. So does it mean I can achieve it by
>> zeroing out a bandpass filter made with [biquad~]? Cause I see people make
>> bandpass filters with 2poles in biquad, but the zeros are at -1 and 1. I
>> tried zero values of zero, but it didn't look to good to make me believe
>> that's the same as [bp~].
>>
>>  I know of miller's example H10.measurement.pd, and compared to it,
>> didn't seem to fit.
>>
>>  Anyway, I wanted something that would plot [bp~] right away, not like
>> the H10 example, which takes some time. But then, if we can't do it with
>> biquad coefficients, I would need some guidelines to do it some other how.
>>
>>  Thanks
>>
>>  Cheers
>>
>>  I know about filterview and patch
>>
>>
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>
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