Commision a Resonance Filter

[Lemyisgod]

Hey Im wondering if anyone knows how to build a Resonance Filter. On a Boss ME-50 pedal attached to the wah theirs a setting called Resonance (Which I think is similar to a Low Pass Filter). I need a stand alone version of that pedal. It sounds like a old synth filter. I don't need it to sweep but just act as a filter that I can turn on and off for Lo-Fi parts of my songs. Dragging around a ME-50 just for that one effect is a gigantic pain.

Heres a sample of me sweeping the filter so you can get an idea of what Im talking about. http://www.reverbnation.com/play_now/song_8265101

[John Lyons]

I think you would be best off with a parametric EQ.
The sound you linked isn't just a low pass filter.
A LPF is basically a treble control not unlike the bass side
of a big muff tone control.
The sample linked is sweeping through frequencies not just
passing low end at a fixed frequency.

[eatyourguitar]

the sound of digital filters are pretty bad IMO. some people can't tell the difference but I can. the video you posted has a LFO controlling the LPF frequency. like John says, it is sweeping up and down.

[youtube]http://www.youtube.com/watch?v=AbVALRqLPSw[/youtube]

I'm really not sure if they have an LFO built in but the regular xerograph has an expression pedal input. this might be better than a LFO. anyway, resonance is just one of the two knobs you see on every filter. it does not always need to be a lowpass filter. but the one you posted is a low pass filter with only a little resonance set on the knob. if you turn the resonance up, they just scream @ the resonant frequency. some filters can produce sound with no input if the resonance is turned all the way up. I found a ms20 schematic that was modified to run on +9v. its doable but I'm super busy right now.

[John Lyons]

...the video you posted has a LFO controlling the LPF frequency

...me sweeping the filter

Just sayin'.

[Lemyisgod]

I know the sample I posted has sweeping. I was sweeping the pedal so you can hear what it sounded like. It was sweeping from a almost clean setting to what sounds like underwater. A EQ wont do what I want it too. Its the same Resonance effect thats on old Korg analog synths (or is it moogs?)

[Lemyisgod]

http://www.reverbnation.com/play_now/song_8251279 - Here its set at a fixed interval (sorry about the clipping). It sounds more muffled and kinda like an underwater effect. Thats what Im looking for. Just a filter I can set and turn on and off.

[eatyourguitar]

oh yeah, just get the regular xerograph. the sound your after is a low pass filter. it does not matter that korg or moog have made low pass filters. there are some differences between them but I don't think it is something to loose sleep over.

[Lemyisgod]

Can you set the Xenograph not to sweep when playing threw it and use it as a fixed filter?

[Gone Fission]

Buy a Korg Monotron just to use the filter on the external input?

[Lemyisgod]

Ha I was actually thinking that and then hooking it up to a bypass loop. The output is too noisy though.

[John Lyons]

A EQ wont do what I want it too.

A parametric EQ has high pass, low pass and bandpass filtering.
It will do anything you set it to do.
The basis for all filtering is Equalization.
Changing any signal's frequency response, level or bandwidth is Equalization.
http://en.wikipedia.org/wiki/Parametric_equalization#Parametric_equalizer
Filter sweeping is a parametric EQs strong point.

[eatyourguitar]

not all EQ's have enough attenuation per band to get negative infinity Db where you want. this was a huge problems with DJ mixers in the late 90's. most DJ's had 3 band EQ but did not have the LPF they wanted. naturally we were all beating the shit out of the 3 band thingy but it was never really cool until vestax and rane came out with a 3 band EQ that was capable of -48Db on each band. the most basic adjustable RC filter is a cap and a pot. the slope of a lowpass or highpass filter is written as DB reduction per octave. because the attenuation increases or decreases with every octave, a LPF will completely eliminate anything 3 or 4 octaves up. and yes the iron ether xerograpg (not the deluxe) is just two knobs, fixed lowpass filter. exactly what you want. it also has an expression pedal input you might use someday. there are 1,227,096 filters you can buy but the xerograph is the only one I can think of that is just a basic adjustable low pass filter. you could do it with any auto wah pedal if you tweak the knobs just right but that is almost a waste of money if you don't need autowah.

[D-Rainger]

There's always this http://www.raingerfx.com/compactotron%20c-2.html. Can be parked at a frequency. However it does have a distortion circuit in action all the time... Just thought I'd mention (in a not too self-promoting way).

[Lemyisgod]

I have two parametric EQs and neither will get the sounds I want it too.
EatYourGuitar - Your not the first to recomend a xerograph to me me for the same sort of sound. No wah Ive ever played can get this exact sound. Its a really bizarre filter that Boss added on this one Multi effects Unit. If you ever come across a ME-50 just set up the wah on the Resonance filter and play around with it it doesn't sound anything like a Wah. Really the only thing it sounds like is a old analog synth filter.

[eatyourguitar]

Well the clip you posted sounds like a low pass filter with the resonance about half way up. Thats all it is. The me-50 is digital. Analog just sounds like the analog filters in a synth, or dj effects. Analog filters are not hard to make.