Support

If you have a problem or need to report a bug please email : support@dsprobotics.com

There are 3 sections to this support area:

DOWNLOADS: access to product manuals, support files and drivers

HELP & INFORMATION: tutorials and example files for learning or finding pre-made modules for your projects

USER FORUMS: meet with other users and exchange ideas, you can also get help and assistance here

NEW REGISTRATIONS - please contact us if you wish to register on the forum

Users are reminded of the forum rules they sign up to which prohibits any activity that violates any laws including posting material covered by copyright

Tilt filter, "blue-ing" filter (cough cough martin?)

DSP related issues, mathematics, processing and techniques

Re: Tilt filter, "blue-ing" filter (cough cough martin?)

Postby guyman » Fri Sep 28, 2018 4:45 pm

btw that schematic is currently only :D and not :(
User avatar
guyman
 
Posts: 207
Joined: Fri Mar 02, 2018 8:27 pm

Re: Tilt filter, "blue-ing" filter (cough cough martin?)

Postby martinvicanek » Sat Sep 29, 2018 7:14 pm

I uploaded version 2 in the original post above.

@Adam, this was actually my first thought: I nailed the transfer function at 1 kHz. However, I realized that if you tilt whichever direction, you'll overflow the next stage. I found it annoying to have to adjust the volume each time I changed the slope. HTat's why I chose the other normalization, with pink noise resembling (very roughly) a musical source.

@guyman, not quite sure what exactly you want to achieve?
User avatar
martinvicanek
 
Posts: 1328
Joined: Sat Jun 22, 2013 8:28 pm

Re: Tilt filter, "blue-ing" filter (cough cough martin?)

Postby guyman » Sun Sep 30, 2018 5:44 pm

I want to create a smile/frown (low/high boost cut) filter consistent with both the db/octave law of power, and normalization technique you are implementing in these filters. Let's say 0/db per octave is x, or our input signal, unaltered across the spectrum. in one instance we tilt it y db resulting in both + and - gain changes, and in another instance we tilt it -y db resulting in both + and - gain changes. Again like you emphasized before this is not relevant to a changeable "center frequency" but to your approach to normalization (not sure I fully understand - which may be the root of me missing this whole thing.)

In my smile, or low/high boost filter, you tilt the filter both +-y db from x, but only keep the corresponding +gain changes from both tilts, and vice versa with the frown/ low/high cut filter. you keep the -y gain changes from x from -+y tilt.

like let's say you have purple noise (+6db/oct) and brown noise (-6db/oct), on the smile filter you would have the positive high frequency gain changes from the +6db/purple tilt, and the positive low frequency gain changes from the -6db/brown noise tilt, resulting in a boosting filter that is consistent to the spectrum.

perhaps I lack the language to articulate it, or my imagination has run far too rampant.

I'm going to fiddle with your updated schematics and see what's going on.
Last edited by guyman on Sun Sep 30, 2018 6:48 pm, edited 1 time in total.
User avatar
guyman
 
Posts: 207
Joined: Fri Mar 02, 2018 8:27 pm

Re: Tilt filter, "blue-ing" filter (cough cough martin?)

Postby guyman » Sun Sep 30, 2018 6:01 pm

Actually my imagination is not failing me. This is a hyper-relevant tone nob, consistent with the laws of power and our hearing.
User avatar
guyman
 
Posts: 207
Joined: Fri Mar 02, 2018 8:27 pm

Re: Tilt filter, "blue-ing" filter (cough cough martin?)

Postby guyman » Sun Sep 30, 2018 10:36 pm

Is something like LU normalization possible?
User avatar
guyman
 
Posts: 207
Joined: Fri Mar 02, 2018 8:27 pm

Re: Tilt filter, "blue-ing" filter (cough cough martin?)

Postby guyman » Sun Nov 11, 2018 11:55 pm

Do you have a copy of the one that's nailed to 1k? I am assuming it doesn't have normalization.
User avatar
guyman
 
Posts: 207
Joined: Fri Mar 02, 2018 8:27 pm

Previous

Return to DSP

Who is online

Users browsing this forum: No registered users and 52 guests