KVR Audio

spacedad · Post by **spacedad** » Fri May 04, 2012 1:58 pm

could someone point me in the right direction,please.
i'm trying to make a zap machine,like my korg ms20.
(you could turn down the volume of the oscillators but have an independent peak knob for the rez.)
i've got the white noise connected to the filter with the rez turned up,but if i turn down the volume of the white noise it won't trigger the filter.

aciddose · Post by **aciddose** » Fri May 04, 2012 2:07 pm

that's normal. the ms-20 works because the feedback level is greater than 1. in software this produces horrible aliasing.

what you can do is input a pulse. if you want to immediately set the phase of the filter however you need to do that - set the phase of the filter.

for example you might do:

integrator[0] = sin(radians) * scale
integrator[1] = cos(radians) * scale

might not be possible in se without creating a custom filter with a "trigger" event input.

spacedad · Post by **spacedad** » Fri May 04, 2012 3:44 pm

thanks for the quick response.
i'm not sure i fully understand.
i tried a monostable pulse but doesn't seem to work.
how about using sine osc's instead of using the filters rez,is that basically the same thing?

odo · Post by **odo** » Fri May 04, 2012 3:59 pm

I also don't understand it But thats me

Maybe a adsr -> pitch osc ?
Just the a to get the zip sounds

xoxos · Post by **xoxos** » Fri May 04, 2012 5:15 pm

spacedad wrote: i tried a monostable pulse but doesn't seem to work.

you've got it. the sine/cosine computation would only set the right gain and phase over using a plain 1 sample trigger of arbitrary gain.

sine = same thing, generally. what you're doing is like the kicks in swish2, which use self-resonating rbj biquad bandpasses.

spacedad · Post by **spacedad** » Fri May 04, 2012 6:29 pm

i like swish2,but i wanted to try make one that was as easy to use as my ms-20.
you can sweep the LP and HP filters to find the sweet spot,then use both peak rez's with slightly different cut-offs.

by 'rbj' do you mean Rick Jelliffe?

i'll try using sines insted and see.

cheers peeps.

xoxos · Post by **xoxos** » Sat May 05, 2012 5:19 pm

rbj = robert bristow-johnson, author of "biquad cookbook" pdf, so i usually refer to these as the rbj biquads

spacedad · Post by **spacedad** » Sat May 05, 2012 7:26 pm

i see.ok,cool.

i can't get on today,but i was thinking about how sines/rez may behave differently.
using sine osc's will make thinks behave more predictably,
but with filters+rez,as the peaks are increased,i seem to remember them fading and battling in unpredictable ways.
am i remembering correctly?
or should sine osc's work the same way do you think?

aciddose · Post by **aciddose** » Sat May 05, 2012 9:19 pm

it depends on the filter.

spacedad · Post by **spacedad** » Sat May 05, 2012 10:09 pm

ah,
i was using SE's SV LP and HP.
also toying with rick jelliffe's filter4.

i'm guessing using very high frequency (above human hearing) osc to trigger filters would be a bad idea?

maybe there's a 3rd party filter out there,with triggering possibilities....

spacedad · Post by **spacedad** » Wed May 09, 2012 2:04 pm

getting there with sines,cheers...
edit:changed gui a bit.

odo · Post by **odo** » Wed May 09, 2012 2:12 pm

Cool GUi

spacedad · Post by **spacedad** » Wed May 09, 2012 4:25 pm

thanks.hehe.it's still in the workshop,so it may change.

spacedad · Post by **spacedad** » Wed May 09, 2012 4:32 pm

it's not exactly like the ms20,but it's as close as i can get.obviously it's only the zappy bit,not the whole synth.
i want to keep it simple,so i'm still not sure if double lfo's is overkill.
i'm sure it won't be for everyone,but it's just what i need,so there!

odo · Post by **odo** » Wed May 09, 2012 9:10 pm

i looked at your site and so special GUIS so different Gonna try some of yous plug soon
Cheers
Marc

SE:how to trigger filter's resonance only?