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Old Sep 9, 2003, 10:07 AM   #1 (permalink)
Nappylady
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simple question about highshelf

I want to change the EQ Highshelf so that the corner frequency can be selected at more (how to put this) useful values. 12k might be low enough for a Timbre filter, but for drastic EQ without breaking the GPR bank, it really should be startable as low as 1k.

I got into dane and looked, however, and I couldn't see the usual "controls" section. How, exactly, would I go about changing the minimum value on the highshelf filter? If I have to export, then edit, then reimport, I'm fine with that, but please... I really need a lower-reaching highshelf filter.

Thanks in advance.
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Old Sep 9, 2003, 02:36 PM   #2 (permalink)
Lex Nahumury
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The reason you don't see any 'controls' is because this effect is controled by a DLL extension.
To change/set the cuttoff point, about 5 dsp parameters have to be changed 'on the fly'.
This can only be done via an dll extension, not in Dane only.

The only way to change such 'dll-ed' plugins is to re-compile them in C++ using VS6.0 and the SDK.
(See EQ_Highshelf.cpp in the SDK)

Btw; this goes for most filter based effects because of the nr. of simultanious calculated
and updated filter coeffs.

I agree that 12khz is quite high as a minimum value.

/LeMury
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Old Sep 9, 2003, 02:42 PM   #3 (permalink)
Soeren_B
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To modify the ranges of Highshelf you need to go into the source code in the kX SDK and change a few lines in EQ_Highshelf.cpp

The effect was created over a year ago. I think the frequency limitation is within the filter coefficient algorithm, but I can't really remember.

The source code is nicked from www.musicdsp.org

Just search for cookbook

Isn't it possible to acheive HS filter with some of the newer filter plugins (like Max' parametric filter?)

A quick look at the code at my part: The error may be at line 59 where TMP is calculated. Looking at the original source this should only be divided by 40. For some reason this is divided by 400. I should really look into this again


Cheers
Soeren
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Old Sep 9, 2003, 04:12 PM   #4 (permalink)
Nappylady
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Shucks... does that mean I'm SOL? I don't have VC++, and if I did, I'm not any good at it... is there any way one of you guys, or someone else who knows how to do this, could recompile it with a lower min value (perhaps 1k) and send the new DLL to me?
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Old Sep 9, 2003, 05:30 PM   #5 (permalink)
Lex Nahumury
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Quote:
Originally posted by Nappylady
Shucks... does that mean I'm SOL? I don't have VC++, and if I did, I'm not any good at it... is there any way one of you guys, or someone else who knows how to do this, could recompile it with a lower min value (perhaps 1k) and send the new DLL to me?
Well, It is Soeren's source and he already gave you a clue were to look.
(As for VS6; ever heard of 'peer to peer'?..ahuuumm. )

Hmmm...maybe Soeren will fix it. (as I understood from his post)

/LeMury
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Old Sep 9, 2003, 07:46 PM   #6 (permalink)
Nappylady
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Hope so. I've already gone up some steep learning curves and I'd hate to have to go up another one between now and tomorrow afternoon!

As it stands, I'm using a 10-band EQ to get what I need done, except it takes 88 GPR registers, where the highshelf itself takes only 20--I could use 2 highshelves and a lowshelf to get what I need and save 28 registers. Since GPR's are at an extreme premium in my system, conserving them is a Good Thing! I *need* to simplify in order to drive my entire sound system.

Thanks for all the help guys, you've given me tons of information in a short period of time... more than I expected, actually. Well-done!
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