[NewBuyer]

Curious please, and using the 85Hz filters for reference:

Will the frequency output from these filters be down 0db at 85Hz, and down 6db at approx 40Hz? Is that roughly how these work?

Also wondering please about the resistive loading of the filters. Specifically please, what roughly are their input and output impedances? 

[Mike Dzurko]

The 85Hz filters should be down approx. 3db at 85Hz, and 9db at 42.5Hz. The resistance of a filter varies with frequency with the resistance of a high-pass filter increasing as frequency goes down. All passive filters exhibit some insertion loss, it is usually around 3db with these filters. This isn't really an issue as you just adjust the volume control to compensate. Hope this helps!

[NewBuyer]

The 85Hz filters should be down approx. 3db at 85Hz, and 9db at 42.5Hz. The resistance of a filter varies with frequency with the resistance of a high-pass filter increasing as frequency goes down. All passive filters exhibit some insertion loss, it is usually around 3db with these filters. This isn't really an issue as you just adjust the volume control to compensate. Hope this helps!

Yes this does help, thanks!

Does this translate to the 65Hz version filters too - i.e. down 3db at 65Hz and 9db at approx 32.5Hz?

Also still wondering please about their input/output impedance values...

[Mike Dzurko]

Yes that is correct, the 65Hz filter follows that approx. curve. As I said before, the impedance will vary with frequency. I don't recall ever measuring  . . .

[NewBuyer]

Yes that is correct, the 65Hz filter follows that approx. curve. As I said before, the impedance will vary with frequency. I don't recall ever measuring  . . .

Thanks Mike!  I hope you don't think this is a dumb point to make, but please note that your earlier answer referred only to the resistance (not impedance) of your passive high-pass filters. I do understand the variation with frequency, and I do see that you are using the two terms interchangably - was this intentional? If you do determine the input/output impedance values of these filters, it would be nice to know. I usually try to keep a proper impedance ratio between the sources and loads in my system, and have found that some passive line-level devices (filters, attenuators, etc) can be a weak impedance link.

Ok, the passive filters are already -3db at their label frequency. Does that hold true for the crossover on your subwoofer dials too? That is, if I set (both) crossover dials at 45Hz, what attenuation will actually be occurring at 45Hz... will it already be -3db down at the crossover point too (like with the filters), or (?)

[Mike Dzurko]

The subs have dual 12/db/oct filters. Each filter is -3db at the crossover frequency. In tandem, they are -6db at the crossover frequency.

[biz97]

I plan on using some of the 65hz filters in my system as well as some newly purchased Titan XLs(can't wait  ).  Is it right to start the crossovers on the subs at 65hz and adjust from there as necessary?  Or do you use just one?  Thanks.

[Mike Dzurko]

You can download the complete manual in PDF here to get a jump on it    http://www.audioc.com/library1/manuals.htm

The short answer is that yes, I'd start with both filters on the subs around 65Hz and adjust up or down from there using both filters in tandem. It's going to depend a lot on what is happening in your room around that frequency.

[NewBuyer]

The subs have dual 12/db/oct filters. Each filter is -3db at the crossover frequency. In tandem, they are -6db at the crossover frequency.

Thanks again Mike! Good to know and I appreciate it. I never realized that the separate filters, and also the built-in sub crossover filters, were already down these decibals at their cutoff frequencies. I might be the last to know this though, which unfortunately is not uncommon for me.

By the way, for the record, I personally like the ACI passive filters and have never experienced any problems or issues whatsoever with them. They sound great to me, very nice and transparent. I only ask about their input/output impedances for future reference - in case I might someday use them in another system, that is more sensitive to these things than my current one.