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Need formula for eq-knobs

Posted: 12 Jan 2012 17:08
by iPad_User
Hey guys,

sorry for starting another new thread. But according to this thread:

http://liine.net/forum/viewtopic.php?f=24&t=889

I want to replace all the textobjects with a monitor, which shows me the actual Hz value.
So, I've got different knobs, some go from 16-350Hz, some from 0,2-2kHz. So is there a formula, which I can use?

I'm not familiar in scripting thats why I need your help.

Thanks!!

Chris

Re: Need formula for eq-knobs

Posted: 13 Jan 2012 14:49
by Phil999
the first one would be

16+knob.x*334

and the second

0.2+knob2.x*1.8

Re: Need formula for eq-knobs

Posted: 13 Jan 2012 23:45
by iPad_User
Thank you very much!

Now I hope, that the lemur editor gets fixed soon!

Re: Need formula for eq-knobs

Posted: 01 Mar 2012 08:15
by OoGuN
Hi,

new to this as well and trying to make a template to control Harrison Mixbus.

The EQs are mixed, Low goes from 40 - 400Hz, mid from 200Hz - 4kHz, High from 800Hz to 15kHz.

I tried adapting your formula above for the Low one giving me 40+Knob.x*360 and at either end, the values are right. However, when the knob is midway, it reads 224Hz, while the one in Mixbus is 162.2Hz.

Obviously there is something not linear about the way Mixbus knob is split, I'm hoping you would be able to give me the right formula. Or failing that, I would love to know how you arrived at the formulas you gave above (what's the maths) so I can take some time and try to work it out myself (and not have to keep asking, because there are other knobs with different start/end values to do as well)

Thanks in advance, I'd really appreciate any help whatsoever.

Re: Need formula for eq-knobs

Posted: 01 Mar 2012 16:23
by Phil999
OoGuN wrote:However, when the knob is midway, it reads 224Hz, while the one in Mixbus is 162.2Hz.
this is a problem that can't be resolved easily I'm afraid. It would be better to have the parameter name/value readout from the DAW/plugin directly using the Mackie Control protocol, but that isn't easy either.

What I do in these cases is to look at the Lemur values as approximation, and look at the DAW/plugin when I want to know the exact values.

Re: Need formula for eq-knobs

Posted: 01 Mar 2012 21:13
by OoGuN
Thanks Phil999,

I think what I might try (apart from living with the approximation, which is fine) is to ask the Harrison guys what "law" their knobs follow. Its based on Ardour, which is open source and they are pretty good about answering questions.

Cheers

Re: Need formula for eq-knobs

Posted: 01 Mar 2012 21:54
by Phil999
yes, of course. That's a very good idea.

Re: Need formula for eq-knobs

Posted: 02 Mar 2012 22:51
by OoGuN
OK so I spoke to the MIxbus guys and for the Lo band eq knob, this: 40+pow(x,1.5)*360 gives me the right values appearing over my knob in Lemur. However, now when turn the knob in Lemur, the mix bus knob reaches the extreme right when the lemur knob is only about halfway between left and right.

I'm guessing this must be a scaling problem, but I'm not sure how to address it. It's a bit frustrating because I'm sure it's a noob-ish error. Out of interest I tried a TouchOsc template someone had made for Mixbus, which gets the correct response from the Mixbus knob, though he's used sliders instead of knobs to control the Mixbus knobs.

I told the Mixbus guys that the knobs were over a range 0 - 127 before they gave me the formula.

I guess I don't really yet understand how to alter the range a full turn of the knobs in Lemur represent.

By the way, the knobs in Mixbus are not 360 degrees, they are 270 degrees.

Re: Need formula for eq-knobs

Posted: 03 Mar 2012 00:17
by Macciza
Hi
Try sending your original Knob.x equation data as the control and only use the new equation for monitoring purposes and see if that matches up . . .
MM

Re: Need formula for eq-knobs

Posted: 05 Mar 2012 03:18
by OoGuN
Thanks Macciza,

I ended up using a the formula as is, but decided to use Osculator instead of the Lemur Daemon, because that way I was able to set the input range for the knob from 0 to 270 (as I mentioned that is the range of the knobs in Mixbus). This gives me the correct behavior for the knob when I turn the one in Lemur :D

thanks for the suggestions, guys