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High pass filter

My goal is reduce a vertical axial mode at 60Hz produced from my main speakers.  A JL CR1 did the job but produced too much distortion. I have looked at passive and active line-level crossover and filter options, including DEQX. I am interested in an do-it-myself capacitor option like the one on GR Research website but 6db/octave is too shallow. I need a second order at least. Has anyone made a passive high pass filter second order or higher? I believe it is two capacitors in series with the first one ten times the value as the second. My amp is 30Kohm input impedance. I do not if a resistor is necessary. As I type this I have a sense I am going down the wrong rabbit hole. The relatively low cost and ability to alter it is compelling, though. Thanks for any help. 

ohlala
yogiboy's avatar
yogiboy
6,209 posts
 

How about this? I used this years ago with great results!

https://hsuresearch.com/collections/accessories/products/high-pass-filter

knotscott's avatar
knotscott
1,408 posts
 

I know you want a steeper slope, but have you given a first order inline high pass a try?  It's much simpler. I used a silver mica cap, and it works well and sounds wonderful for my application.  

erik_squires
17,599 posts
 

mode at 60Hz

Well the correct answer is a parametric EQ honestly. Even better with bass traps in the right location.  A single cap HP filter is an excellent idea when you are bi-amping but here it's going to just make your system sound too lean.

My suggestion is get an inexpensive miniDSP and try it.  Or if you stream with Roon it has DSP filtering built in. 

If you are just dying to solder something try an LC in series, I think 0.7mH and 100uF could work, I may have done the math wrong, with a variable resistor around 30k-100K pot around the whole thing so you can adjust the dip depth.  You wont get what you really need which is variable filter width but hey, worth playing with. 

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