[PD] [biquad~] as cyclone's [allpass~]?

[Alexandre Torres Porres]

but this way it won't be the same as cyclone's [allpass~], the way I did it
is equivalent to it (and max's).

cheers


2013/10/3 Chris Clepper <cgclepper at gmail.com>

> You only need one delay line for the allpass.
>
> feedforward = input * -gain
> feedback = delayout * gain
> delayin = input + feedback
> output = delayout + feedforward
>
> http://www.spinsemi.com/knowledge_base/effects.html#Reverberation
>
>
> On Thu, Oct 3, 2013 at 11:29 AM, Alexandre Torres Porres <porres at gmail.com
> > wrote:
>
>> i hope i guess i figured it out on how to implement it with delay lines.
>> see attachment. And I realize you can't do this with [fexpr~] or [biquad~]
>> because the sample delay length is kinda big for that, right?
>>
>> cheers
>>
>>
>> 2013/10/3 Alexandre Torres Porres <porres at gmail.com>
>>
>>> cool, but do you know how to implement cyclone's [allpass~] with it?
>>>
>>> It's really unclear to me what is the relation of this pass filter with
>>> the one you can generate with biquad coefficients, or with raw poles/zeros
>>> objects for that matter.
>>>
>>> Well, one way or another, it's also unclear to me how to do it with
>>> delay lines.
>>>
>>> seems that it is related to a comb filter, right?
>>>
>>> cheers
>>>
>>>
>>> 2013/10/2 Chris Clepper <cgclepper at gmail.com>
>>>
>>>> Allpass for reverb is easy to do with delwrite~ and vd~.  I used 32 of
>>>> them today to recreate a famous 'deep space' reverb.
>>>>
>>>>
>>>> On Wed, Oct 2, 2013 at 1:53 AM, Alexandre Torres Porres <
>>>> porres at gmail.com> wrote:
>>>>
>>>>> hi there, i see the biquad's coefficients can be set as an allpass
>>>>> filter, generated by frequency and "Q" parameters. But can it do the same
>>>>> as cyclone's [allpass~] filer? If yes, them how since the parameters for
>>>>> [allpass~] are different (delaytime and such).
>>>>>
>>>>> One way or another, I guess that my real question is: how to implement
>>>>> [allpass~] from vanilla objects?
>>>>>
>>>>> thanks
>>>>>
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>>>
>>
>
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