MPC Ren | Program Mixer's Filter section vs. 0-127 value.

SimonInAustralia wrote:

Airyck wrote:You could still crank the resonance and take some measurements with a spectrum analyzer.

Can you?

Sure, you would see a spike at the cutoff frequency on a spectrum analyzer. You just need a steady tone or noise playing while you are doing it. A self resonating filter would work too but there isn't any of that in the Ren software as far as I know.

Airyck wrote:Sure, you would see a spike at the cutoff frequency on a spectrum analyzer. You just need a steady tone or noise playing while you are doing it. A self resonating filter would work too but there isn't any of that in the Ren software as far as I know.

Not easy to be very accurate (impossible?) with a tone/noise playing while you are trying to measure the resonant frequency.

SimonInAustralia wrote:

Airyck wrote:Sure, you would see a spike at the cutoff frequency on a spectrum analyzer. You just need a steady tone or noise playing while you are doing it. A self resonating filter would work too but there isn't any of that in the Ren software as far as I know.

Not easy to be very accurate (impossible?) with a tone/noise playing while you are trying to measure the resonant frequency.

You can be very accurate, the resonance will be a spike in the spectrum analyzer, you just measure the frequency at the highest (loudest) point for each setting of the filter knob. Also you'd want a full range noise like pink noise.

Airyck wrote:Also you'd want a full range noise like pink noise.

white noise. pink is filtered to match human hearing - good for a listening test, but in this scientific test you are proposing, pure white would be fine.
http://en.wikipedia.org/wiki/Colors_of_noise

i still think there is no point to waste your time on this test, but it is fun sometimes to learn a bit
(i've done this with a hardware to match left and right channels).

Airyck wrote:You can be very accurate, the resonance will be a spike in the spectrum analyzer, you just measure the frequency at the highest (loudest) point for each setting of the filter knob. Also you'd want a full range noise like pink noise.

Cool, will try with white.

Was hoping for a clean resonant tone only, to measure with a frequency counter, rather than trying to guess exactly where the peak is on a spectrum analyzer.

SimonInAustralia wrote:

Airyck wrote:You can be very accurate, the resonance will be a spike in the spectrum analyzer, you just measure the frequency at the highest (loudest) point for each setting of the filter knob. Also you'd want a full range noise like pink noise.

Cool, will try with white.

Was hoping for a clean resonant tone only, to measure with a frequency counter, rather than trying to guess exactly where the peak is on a spectrum analyzer.

simon if you crank the resonance up enough, you should be able to break through the noise.

we're talking digital here, you could turn the noise down pretty low and still get a good reading.

if yall are just joining us - white noise is composed of every frequency in the spectrum, so its a good analysis tool.

tapedeck wrote:simon if you crank the resonance up enough, you should be able to break through the noise.

we're talking digital here, you could turn the noise down pretty low and still get a good reading.

Yeah, will give it a try when I get a chance.

I did try previously with a blank sample, just recorded in Sample Record mode with no input, but it didn't trigger the envelope/filter/etc. when played at all, so no filter resonance to measure.

Will try with various levels of white noise.

SimonInAustralia wrote:I did try previously with a blank sample, just recorded in Sample Record mode with no input, but it didn't trigger the envelope/filter/etc. when played at all, so no filter resonance to measure.

Will try with various levels of white noise.

yea youd definitely need the noise as source signal for the effect to work with.

it is really telling to 'see' how your various gear behaves. i use this method to calibrate the left and right channels of my hardware exciter.
its also really handy to 'see' the charteristics of a microphone / speaker, by playing white noise into the mic and watching the output (helps to have an isolated control room).

a really handy tool.
one other fun fact is that whitenoise is basically a collection of random values from -1 to +1. if you told a computer to generate random values and listened to it, you'd get noise.