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EEQ-12 Elliptic Equalizer Construction Information

Posted: Sat Oct 28, 2017 2:44 pm
by mediatechnology
This thread documents construction of the EEQ-12 Elliptic Equalizer.

Update June 20, 2021: Assembly, Schematics and Test Instructions: ... 2021_1.pdf

Elliptic Equalizer EEQ-12 PC Boards: ... search=EEQ



Sheet 1: ... heet_1.png
Sheet 2: ... heet_2.png

Circuit Description: viewtopic.php?f=6&t=828&start=46

Mouser Project Manager BOM for the EEQ-12 Elliptic Equalizer 24V Relays: ... 470f9f152e
(includes THAT and NJR ICs)

Board Stuffing Diagram:

Image ... ut_800.jpg

Re: EEQ-12 Elliptic Equalizer Construction Documents

Posted: Thu Nov 01, 2018 4:04 pm
by mediatechnology
Blog post from Ian Stewart on Elliptic EQ:
KA-Electronics EEQ-12: Among the minimum phase alternatives, the KA-Electronics EEQ-12 is the standout. This analog DIY device, designed and sold by Wayne Kirkwood, manages a 12dB/octave slope without the negative affects of phase shift usually associated with higher order filters. In a nutshell, he does this by compensating with cleverly designed all-pass filter network. If you’re interested in further reading on this device, you can see the design process here. Worth noting, the EEQ-12 tested uses a cutoff frequency of 150Hz rather than the 100Hz setting chosen for all other processors. Even so, it achieves better separation in both the frequency and stereo spaces, and with less phase shift to boot, than any of its 6dB/octave minimum phase elliptical EQ cousins.

Re: EEQ-12 Elliptic Equalizer Construction Documents

Posted: Sun Aug 23, 2020 5:46 pm
by mediatechnology
Update July 28, 2020: Assembly and Test Instructions: ... 2820_1.pdf