Voltage Controlled State Variable Filter

gabbagabi

Hi,

I had this on the Breadboard yesterday.
Normally i would do more testing before posting, but there is a other thread talking about this. May it can be usefull.

Cheers BB,
gabbagabi

gabbagabi_voltage_controlled_state_variable_filter_schemo.png

Description:

Filesize:

87.02 KB

Viewed:

1144 Time(s)

This image has been reduced to fit the page. Click on it to enlarge.

J3RK · Joined: Jun 05, 2006 Posts: 123 Location: Seattle

Nice! I love the simplicity there. I wonder if you can do voltage controlled resonance using a transistor as well.

gabbagabi · Posted: Wed Feb 22, 2017 6:20 am Post subject:

thx J3RK,
simplicity is what iam searching for,
for me this is where all the beauty and joy in the world is coming from Let us pray

i have tried this on the breadboard today, with some success.

LP_out.png

Description:

Filesize:

29.67 KB

Viewed:

14790 Time(s)

gabbagabi_voltage_controlled_state_variable_filter_with_CV_RESO_schemo.png

Description:

Filesize:

94.57 KB

Viewed:

969 Time(s)

This image has been reduced to fit the page. Click on it to enlarge.

Sebo · Joined: Apr 27, 2007 Posts: 564 Location: Argentina

Nice circuit, i will try it.

I think that the HP Out is missing in the second circuit...

gabbagabi · Posted: Mon Feb 27, 2017 10:39 am Post subject:

thx,
i guess u have to apply a offset to the resonace-part also, and play with the resistor values that are on top of the cv pots (R12 & R44)
and u can try to ommit R7 or R37

the hp output was meant symbolic like: connect the green "wires", now i see that there are two green, what a shame Smile

L´Andratté · Posted: Sun Apr 30, 2017 3:03 am Post subject:

Very nice g.gabba!
This configuration is very nice, because I´m in the back of my head thinking about a synth which can be built with garden variety components exclusivly. I think the Monotribe filter does this vc with bjts also in a SallenKey topology.
I would be very interested in a sound sample Wink

Cheers

gabbagabi · Posted: Fri May 05, 2017 11:49 am Post subject:

thx for the flowers,
i did soundsamples but the quality is embarassing,
they are taken from the breadboard in to the mic-in from the laptop,
there are a lot of humm&brumm

i only had that on breadboard, so no garanty for results on a proper board

cheers, gabbagabi
ps: may u like this also http://electro-music.com/forum/topic-66911.html

svf_bp.mp3

Description:

Filesize:

1.17 MB

Viewed:

1547 Time(s)

svf_hp.mp3

Description:

Filesize:

520.41 KB

Viewed:

1444 Time(s)

svf_lp.mp3

Description:

Filesize:

1.38 MB

Viewed:

1538 Time(s)

gabbagabi · Posted: Sun May 28, 2017 1:59 am Post subject:

why the the reality can not always be so nice like in simulation?

and why i dont have a real 4-Channel Tektronixxxx?

gAbBagabI_simple_voltage_controlled_svf.png

Description:

Filesize:

44.89 KB

Viewed:

833 Time(s)

This image has been reduced to fit the page. Click on it to enlarge.

@LP_OUT_gAbBagabI_simple_voltage_controlled_svf_CUTOFF_mod.gif

Description:

Filesize:

193.31 KB

Viewed:

740 Time(s)

This image has been reduced to fit the page. Click on it to enlarge.

@LP_OUT_gAbBagabI_simple_voltage_controlled_svf_RES_mod.gif

Description:

Filesize:

208.81 KB

Viewed:

738 Time(s)

This image has been reduced to fit the page. Click on it to enlarge.