Derek,

Thanks for the complete list! This is very helpful.

I was hoping to start off by using Vanilla-only objects. Does anyone have some good examples of how [biquad~] can be used to replicate standard low/high/band pass filters w/ q? Any other ideas?

~brandon

On Sun, May 17, 2009 at 4:35 AM, Derek Holzer derek@umatic.nl wrote:

Hi Brandon,

here ya go!

VANILLA PD

*SIGNAL CONTROLLED*

vcf~ moog~

*MESSAGE CONTROLLED*

lop~ bp~ hp~ biquad

PD-EXTENDED/EXTERNAL LIBRARIES

*SIGNAL CONTROLLED*

---IEM Lib filters---

vcf_filter~ (building block for following abstractions)

vcf_bp2~ vcf_bp4~ vcf_bp6~ vcf_bp8~

vcf_hp2~ vcf_hp4~ vcf_hp6~ vcf_hp8~

vcf_lp2~ vcf_lp4~ vcf_lp6~ vcf_lp8~

vcf_rbp2~ vcf_rbp4~ vcf_rbp6~ vcf_rbp8~

*MESSAGE CONTROLLED*

---IEM Lib filters---

filter~ (building block for following abstractions)

bpq2~ bpw2~ bsq2~

hp1~ hp2~ hp2_bess~ (can go from 2-10 order) hp2_butt~ (can go from 2-10 order) hp2_cheb~ (can go from 2-10 order) hp2_crit~ (can go from 2-10 order)

lp1~ lp2~ lp2_bess~ (can go from 2-10 order) lp2_butt~ (can go from 2-10 order) lp2_cheb~ (can go from 2-10 order) lp2_crit~ (can go from 2-10 order)

---GGEE---

(Generate biquad coefficients) bandpass highpass lowpass

Maybe I missed some? ;-)

Best! D.

brandon zeeb wrote:

...

Hallo,

How does everyone implement basic resonant filters, ie: LPF, HPF, BPF, in Puredata? [lop~], [hip~], and [bp~] are nice, and can easily be strung serially to create 2nd, 3rd, and 4th order filters, but lack q.

[biquad~] seems up to the task, but I'm unable to find any information in the help file or docs online pertaining to how one could replicate standard filters using this object.

-- ::: derek holzer ::: http://blog.myspace.com/macumbista ::: http://www.vimeo.com/macumbista ::: ---Oblique Strategy # 164: "Twist the spine"

I think if you Google "biquad filter coefficients" or similar, you'll come up with tons of Greek to play with. Otherwise, the GGEE objects merely do the calculations and export them as messages, so if you wanted to use these objects to get some reasonable sounding stuff and then build your vanilla filters based on those coefficients, the filters themselves are technically vanilla as well.

best! D.

brandon zeeb wrote:

Derek,

Thanks for the complete list! This is very helpful.

I was hoping to start off by using Vanilla-only objects. Does anyone have some good examples of how [biquad~] can be used to replicate standard low/high/band pass filters w/ q? Any other ideas?

~brandon

On Sun, May 17, 2009 at 4:35 AM, Derek Holzer <derek@umatic.nl mailto:derek@umatic.nl> wrote:

Hi Brandon,

here ya go!

VANILLA PD

*SIGNAL CONTROLLED*

vcf~
moog~

*MESSAGE CONTROLLED*

lop~
bp~
hp~
biquad

PD-EXTENDED/EXTERNAL LIBRARIES

*SIGNAL CONTROLLED*

---IEM Lib filters---

vcf_filter~ (building block for following abstractions)

vcf_bp2~
vcf_bp4~
vcf_bp6~
vcf_bp8~

vcf_hp2~
vcf_hp4~
vcf_hp6~
vcf_hp8~

vcf_lp2~
vcf_lp4~
vcf_lp6~
vcf_lp8~

vcf_rbp2~
vcf_rbp4~
vcf_rbp6~
vcf_rbp8~

*MESSAGE CONTROLLED*

---IEM Lib filters---

filter~ (building block for following abstractions)

bpq2~
bpw2~
bsq2~

hp1~
hp2~
hp2_bess~ (can go from 2-10 order)
hp2_butt~  (can go from 2-10 order)
hp2_cheb~  (can go from 2-10 order)
hp2_crit~  (can go from 2-10 order)

lp1~
lp2~
lp2_bess~  (can go from 2-10 order)
lp2_butt~  (can go from 2-10 order)
lp2_cheb~  (can go from 2-10 order)
lp2_crit~  (can go from 2-10 order)

---GGEE---

(Generate biquad coefficients)
bandpass
highpass
lowpass

Maybe I missed some? ;-)

Best!
D.



brandon zeeb wrote:

    Hallo,

    How does everyone implement basic resonant filters, ie: LPF,
    HPF, BPF, in Puredata?  [lop~], [hip~], and [bp~] are nice, and
    can easily be strung serially to create 2nd, 3rd, and 4th order
    filters, but lack q.

    [biquad~] seems up to the task, but I'm unable to find any
    information in the help file or docs online pertaining to how
    one could replicate standard filters using this object.


-- 
::: derek holzer ::: http://blog.myspace.com/macumbista :::
http://www.vimeo.com/macumbista :::
---Oblique Strategy # 164:
"Twist the spine"

Yeah, that's the one I was thinking of, but was too busy doing taxes to remember the name ;-)

best! D.

brandon zeeb wrote:

http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt

Hey,

I've implemented the same coefficients as the ggee [lowpass] external in Pd, and can't seem to figure out where my calculations are off. The calculations are in the [pd lowpass] sub patch.

Any ideas? ~Brandon

On Sun, May 17, 2009 at 2:43 PM, Frank Barknecht fbar@footils.org wrote:

Hallo, brandon zeeb hat gesagt: // brandon zeeb wrote:

...

Good call! I explored the GGEE objects in Pd-extended, which led me to their source code (A+ for readability), which led me to this: http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt

The filter objects in the rjdj-lib just do these calulations as pd-vanilla abstractions (no stability checks)

Ciao

Frank

---

Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list

Derek Holzer wrote:

VANILLA PD

*SIGNAL CONTROLLED*

vcf~ moog~

is moog~ really in vanilla? (not here (0.42-5), unforunately, though i think it should be...)

bis denn! martin

there is also bq~ in the nusmuk floder + all abstraction to compute the filter coef. bq~ is a simple biquad, but with audio input for filter coefs.

C

Derek Holzer a écrit :

Hi Brandon,

here ya go!

VANILLA PD

*SIGNAL CONTROLLED*

vcf~ moog~

*MESSAGE CONTROLLED*

lop~ bp~ hp~ biquad

PD-EXTENDED/EXTERNAL LIBRARIES

*SIGNAL CONTROLLED*

---IEM Lib filters---

vcf_filter~ (building block for following abstractions)

vcf_bp2~ vcf_bp4~ vcf_bp6~ vcf_bp8~

vcf_hp2~ vcf_hp4~ vcf_hp6~ vcf_hp8~

vcf_lp2~ vcf_lp4~ vcf_lp6~ vcf_lp8~

vcf_rbp2~ vcf_rbp4~ vcf_rbp6~ vcf_rbp8~

*MESSAGE CONTROLLED*

---IEM Lib filters---

filter~ (building block for following abstractions)

bpq2~ bpw2~ bsq2~

hp1~ hp2~ hp2_bess~ (can go from 2-10 order) hp2_butt~ (can go from 2-10 order) hp2_cheb~ (can go from 2-10 order) hp2_crit~ (can go from 2-10 order)

lp1~ lp2~ lp2_bess~ (can go from 2-10 order) lp2_butt~ (can go from 2-10 order) lp2_cheb~ (can go from 2-10 order) lp2_crit~ (can go from 2-10 order)

---GGEE---

(Generate biquad coefficients) bandpass highpass lowpass

Maybe I missed some? ;-)

Best! D.

brandon zeeb wrote:

...

Hallo,

How does everyone implement basic resonant filters, ie: LPF, HPF, BPF, in Puredata? [lop~], [hip~], and [bp~] are nice, and can easily be strung serially to create 2nd, 3rd, and 4th order filters, but lack q.

[biquad~] seems up to the task, but I'm unable to find any information in the help file or docs online pertaining to how one could replicate standard filters using this object.