EEQ-12 Elliptic Equalizer Construction Information

Construction information for DIY projects, including the MS Mid Side Matrix, Elliptic Equalizer, Mastering Console, Phono Transfer System, Insert Switcher and the Dual Class-A Amplifier. You can post your baby pictures here.
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mediatechnology
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EEQ-12 Elliptic Equalizer Construction Information

Post by mediatechnology » Sat Oct 28, 2017 2:44 pm

This thread documents construction of the EEQ-12 Elliptic Equalizer.

Update June 20, 2021: Assembly, Schematics and Test Instructions: https://ka-electronics.com/images/pdf/E ... 2021_1.pdf

Elliptic Equalizer EEQ-12 PC Boards: https://ka-electronics.com/shop/index.p ... search=EEQ

Image

Schematics:

Sheet 1: https://www.ka-electronics.com/images/p ... heet_1.png
Sheet 2: https://www.ka-electronics.com/images/p ... 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: https://www.mouser.com/ProjectManager/P ... 470f9f152e
(includes THAT and NJR ICs)

Board Stuffing Diagram:

Image

https://www.proaudiodesignforum.com/ima ... ut_800.jpg
https://ka-electronics.com

Covidland (The Movie) Part 1: Lockdown https://banned.video/watch?id=615f96b3aa816336dbd21792

Directing Orson Welles: "What Is It That You Want?": https://waynekirkwood.com/content/Orson ... u_Want.mp3
Americas Frontline Doctors Lawsuit Motion For Preliminary Injunction Of Covid-19 Vaccine Emergency Use Authorization: https://waynekirkwood.com/images/pdf/Am ... zation.pdf

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mediatechnology
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Joined: Sat Aug 11, 2007 2:34 pm
Location: Oak Cliff, Texas
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Re: EEQ-12 Elliptic Equalizer Construction Documents

Post by mediatechnology » Thu Nov 01, 2018 4:04 pm

Blog post from Ian Stewart on Elliptic EQ: http://ianstewartmusic.us/blog/center-that-sub
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.
https://ka-electronics.com

Covidland (The Movie) Part 1: Lockdown https://banned.video/watch?id=615f96b3aa816336dbd21792

Directing Orson Welles: "What Is It That You Want?": https://waynekirkwood.com/content/Orson ... u_Want.mp3
Americas Frontline Doctors Lawsuit Motion For Preliminary Injunction Of Covid-19 Vaccine Emergency Use Authorization: https://waynekirkwood.com/images/pdf/Am ... zation.pdf

User avatar
mediatechnology
Posts: 4892
Joined: Sat Aug 11, 2007 2:34 pm
Location: Oak Cliff, Texas
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Re: EEQ-12 Elliptic Equalizer Construction Documents

Post by mediatechnology » Sun Aug 23, 2020 5:46 pm

Update July 28, 2020: Assembly and Test Instructions: https://ka-electronics.com/images/pdf/E ... 2820_1.pdf
https://ka-electronics.com

Covidland (The Movie) Part 1: Lockdown https://banned.video/watch?id=615f96b3aa816336dbd21792

Directing Orson Welles: "What Is It That You Want?": https://waynekirkwood.com/content/Orson ... u_Want.mp3
Americas Frontline Doctors Lawsuit Motion For Preliminary Injunction Of Covid-19 Vaccine Emergency Use Authorization: https://waynekirkwood.com/images/pdf/Am ... zation.pdf

User avatar
mediatechnology
Posts: 4892
Joined: Sat Aug 11, 2007 2:34 pm
Location: Oak Cliff, Texas
Contact:

Re: EEQ-12 Elliptic Equalizer Construction Information

Post by mediatechnology » Mon Aug 16, 2021 4:35 pm

Just remembered this 2018 post from Ian Stewart on Flotown Mastering's blog.
CENTER THAT SUB! (A GUIDE TO MONOING YOUR LOW END)

VIABLE ELLIPTICAL FILTERS

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.

https://flotownmastering.com/blog/center-that-sub
https://ka-electronics.com

Covidland (The Movie) Part 1: Lockdown https://banned.video/watch?id=615f96b3aa816336dbd21792

Directing Orson Welles: "What Is It That You Want?": https://waynekirkwood.com/content/Orson ... u_Want.mp3
Americas Frontline Doctors Lawsuit Motion For Preliminary Injunction Of Covid-19 Vaccine Emergency Use Authorization: https://waynekirkwood.com/images/pdf/Am ... zation.pdf

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