[rosconey]

i just ordered a pair for my sub-anyone try these yet

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=266-252

[Russtafarian]

I use a similar in-line high pass filter from ACI www.audioc.com between my pre and power amp. It's rated at -6db per octave @65Hz.  ACI also has a 85Hz filter.  

It works very well for me in that my room has a huge bass boosting room mode at about 40Hz.  The filters roll off the bass in my main speakers so they don't excite the 40Hz room mode.  I can then tune my Beringer PEQ/Hsu sub to flatten the room response of the sub.

[Jon L]

i just ordered a pair for my sub-anyone try these yet

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=266-252

I don't understand how they can label them at a certain frequency, 75Hz, 60Hz, etc, b/c the X-over frequency will change depending on input impedance of the amp.  What these "filters" are essentially a capacitor inside the RCA plugs.  You chose the x-over frequency, then calculate the capacitance of the cap you need.

Capacitance(microfarad)=159,155/(x-over frequencyXamp input impedance)

They must be approximating, assuming the typical input impedance of 25-50Kohms of most amps.  

If you've used these, you will notice a VERY slow slope since it's 6dB per octave only.  It really is not a good filter at all.  IMO, you need at least 12dB, preferablly 18dB slope for more seamless blend and coherence.  I tried for a long time to blend this type of filter on top and active x-over for bass without success.  I am much happier after I went all-active.

[rosconey]

they are a 12 db slope-at least the web page says so-
i figured if they dont work well for home audio  i can still use them in the subs i am making for my work van

at that point i will try the berhinger 2way with sub out and use the out for sub duty

[doug s.]

i dunno how well the low-pass filters would work for subs - seems too much like a hit-or-miss proposition.  re: aci's hi-pass filters, according to aci, they are resistively loaded, so i dunno whether or not they use capacitors, or only resistors.  i'm sure a fone call would get the answer.  and, they seem like a good way to get a blend w/monitors that would otherwise be run full range, when using active powered subs, that have wariable wolume & x-over frequencies.  i am considering trying a pair myself, to relieve my proac ref-8-sigs from the stress of those lowest frequencies, when used w/a pair of yamaha yst-305 subs...

doug s.