DSP Robotics Support

I don't know if anyone has done this already, but I tricked out Martin's linear phase 4-band parametric with one of my corny, vintage-y GUIs, and added some extra functionality.

My main use for EQs is mastering my classical recordings, and I just became aware that linear phase EQs are the primary recommendation for that.

I added input Gain and Balance controls, a pair of 18dB/oct LP and HP static filters, with selectable frequencies, a phase inverter, and a stereo width control.

Bands one and two cover 15Hz to 10kHz; bands three and four cover 100Hz to 20kHz.

The first and fourth bands can be switched to first order shelving filters, by clicking on the 'Q' readout labels.

Each band can be bypassed individually (actually just an instant reset to 0dB gain, as I have no idea how to bypass each band separately).

For mastering classical music, a range of +/- 20dB is a bit unwieldy, so the first and fourth bands are +/- 15dB with 1 dB steps, and the second and third bands are +/- 10dB with 1/2 dB steps.

Thanks Martin for yet another brilliant piece of work! (Any additional info on this would be greatly appreciated.)

Nice, Kevin! As always!
One thing: With the HP and LP filters activated, the unit is no longer strictly linear phase, as I am sure you are aware.
If I was to design a linear phase EQ today, I'd probably go the FFT route. One could then easily incorporate HP and LP filters.

Easy for you to say !!

Yes, I assumed the shelving filters were not linear phase, but what, minimum phase?

Here's an update that includes a pretty, if somewhat useless graphic display (but all the fashion these days), partly adapted from the one in your Matched Filters set demo schem; the actual EQ curve display is adapted from the parametric that appeared long ago (anyone know who made that?).




Over on the "New Project Idea" thread, I added a 5-bander with each band including your complete Matched Filters set. In the mold of the Massenburg MDW EQ plugin. Boy, that schem was a real trial - for some reason it wouldn't function using vector knobs, only bitmap ones; any idea why that might be the case? Too many triggers?