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chaos pad controlled filter – incrementation problem

March 15, 2011 | 1:16 pm

Hi everyone,

I have only recently started playing with max and it’s great of fun! However i am having a problem with a chaos pad (pictslider) controlled filter (biquad~). The chaos pad controls the filter fine, i have set the values of the X Y axis’ to their respective values of the filter, the problem im having is the increments the chaos pad uses on the X axis (controlling freq.). i had a similar problem with the Y axis (controlling gain) and corrected it by using a ‘scale’ object so that between the values ’0′ and ’1′ the increments effect the decimal numbers and after ’1′ it effects the integer numbers.

My problem is that i have tried to do something similar with the scale object on the X axis but whatever i do seems to make the ‘pictslider’ object think that i am connecting an inlet rather than effecting the value scale.

– Pasted Max Patch, click to expand. –

This is the patcher in question, any help would be much appreciated!!!

Thanks in advance

Lucas


March 15, 2011 | 4:15 pm

"My problem is that i have tried to do something similar with the scale object on the X axis but whatever i do seems to make the ‘pictslider’ object think that i am connecting an inlet rather than effecting the value scale."

It appears from the way your patch cords are laid out you were *trying* to connect the scale outlet to the pictslider *outlet* – and max always avoids connections like that and in this case forces the patch cord to connect to the inlet. Actually connecting the x scale object – as it was set in your patch to the filtergraph frequency inlet also gave extreme values because the pictslider is already set to output values between 30 and 20000 -. (as set in the pictslider inspector).

I revised the patch to what (I thinkt) you were trying to do – and took liberties to revise both x and y scale object arguments- x scale is only changing the linearity of the values for better low frequency resolution, while y scale is set to achieved balanced cut/boost.

HTH

– Pasted Max Patch, click to expand. –

March 21, 2011 | 4:27 pm

Excelent, this is exactly what i was trying to do, apologies for the bad explination….

So the problem with the routing was because i was trying to route the outlet of the scaling object outputing the scaled number instead of the inlet which is the number to be scaled.

I do have a couple of questions though, is there an easy method to working out the exponential value or is it a case of trial and error or masses of equations? And the ‘low output value’ on the Y axis is set to ’0.0675′ rather than ’0′, is this figure used because of the exponential? if not why not just use ’0′?

Cheers for your help

Lucas


March 22, 2011 | 5:39 am

The exponential value for x (1.0003) was chosen – by trial and error- as it provides somewhat more low frequency ‘resolution’. Much greater values (which you could try) seemed to zip through the lower frequency ranges of the filtergraph or not work at all.

The gain (y) value are a ratio, as you guessed – an exponential, as in a gain fader – where 1 is ‘flat’ or no gain, 12 is (close enough to) max gain, and, to have a proportional gain reduction the min should be 0.833 (ie 1/12) rather than 0.0625 which is 1/16th. either a ratio of 12 or 16 for both gain and cut seems ok, its just that I was not consistent…If you have 0 as a minimum gain value, the ratio becomes extreme and the filtergraph effectively goes ‘out of bounds’.

HTH


March 22, 2011 | 11:27 am

Ok, thanks dude. Appreciate the help!

Lucas


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