I'm in need of a high pass(rumble) filter to go between a DJ mixer and power amp to filter out subsonic signals. Vance Dickason's "Loudspeaker Design Cookbook" mentions two solutions. One is a passive network using two caps and two resistors. He also mentions an active filter kit from Old Colony (#KF-6). The kit is no longer offered, but AudioXpress does sell the PCBs for $10 each and can supply a reprint of the Audio Amateur article.
Has anyone built this kit? If so, is the frequency fixed at 30Hz, or can it be designed for other frequencies? I'd like to implement something centered around ~10Hz.
Disclaimer: I'm strictly a paint by numbers kit builder. While I can "mechanically" read a schematic and measure components, I don't have the ability to interpret schematics or grasp much of the theory.
The KF6 was based on the 4136 opamp. No good. Fred has the right idea, modify another piece. Most EQ and crossovers have high pass filters in them. Rane crossovers have 20hz, 18dB/oct filters. You will need to set the corner to the cut off point of your woofers. This is NOT going to be 10hz. Between 30~40hz with a Qtc of 1~2 is usually appropriate.
don't have LSDC but that passive network may be a good solution and requires no PS - what values are given and nominal Z for the load? - 10Hz is awfully low for active high-pass - usless you're using 16Hz woofers - suspect cascaded Cr-Cr will have 6/9/ then finally 12dB attenuation
Hi G - does the old-c kit pinout Ok with modern op-amps? - one thing you might consider - look on Ebay for EV Interface A or B boxes for ~$10 - those were underdamped 2nd order for ~B6 vented - think you can adjust Q besides F by changing a few parts - Ev should provide the tuning info
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