[krikor]

I'm confused about how the crossover frequencies for the Force Subwoofer are described on the ACI website.  It states in one place:

"Adjustable: 35-250Hz total of 24 db/octave, increasing to 36db/octave"

Elsewhere, the site says:

"Dual 12db/oct. filters individually adjustable for up to 24db/oct. cutoff."


So what does it mean to be "increasing to 36db/oct.?  Does that mean that the crossover slope gets steeper at some point?

Thanks.

[Mike Dzurko]

I'm confused about how the crossover frequencies for the Force Subwoofer are described on the ACI website.  It states in one place:

"Adjustable: 35-250Hz total of 24 db/octave, increasing to 36db/octave"

Elsewhere, the site says:

"Dual 12db/oct. filters individually adjustable for up to 24db/oct. cutoff."


So what does it mean to be "increasing to 36db/oct.?  Does that mean that the crossover slope gets steeper at some point?

Thanks.

Good question The two electrical filters are each 12db/oct. The woofer-cabinet itself exhibits a 12db/oct rolloff starting in the mid 200s. So, combined with the filters, the ultimate slope is 36db/oct.  We should probably take a good look at the wording on our website and revise for clarity. Thanks for asking!

[krikor]

Thanks for the info Mike, that clarifies things.  I recently purchased a pair of your Force subs and love them.

I received a question on another board about the crossover settings and the ability to keep the sub from muddying the midrange.  This is one of the most persuasive attributes of your subs, even when compared to the REL Strata sub.  A comparison I found valuable was to chart their rolloffs at maximum/lowest hz settings, something you may want to add to your site.  (I think I did this right ... frequency doubling with each octave).

FORCE:  -24db @ 70hz, -48db @ 140hz

STRATA: -12 @ 44hz, -24db @ 88hz, -36db @ 176hz, -48db @ 252hz

Even though the REL has a lower crossover minimum xover freq. (22hz), it can't get out of the way of the midrange with only a 12db/oct. slope the way the Force can with its dual xovers!

Thanks for the great subs!

[Mike Dzurko]

Thanks for the info Mike, that clarifies things.  I recently purchased a pair of your Force subs and love them.

I received a question on another board about the crossover settings and the ability to keep the sub from muddying the midrange.  This is one of the most persuasive attributes of your subs, even when compared to the REL Strata sub.  A comparison I found valuable was to chart their rolloffs at maximum/lowest hz settings, something you may want to add to your site.  (I think I did this right ... f ...

You hit the nail on the head. To properly integrate subs with lower order crossovers is far more difficult in my opinion. I've heard a number of times from people who believed that subs were always detrimental to the sound of a well setup two-channel music rig. That opinion changes once you hear subs that were designed for the task. The higher order filters are a big part of what makes it work. Thanks for writing!

[ieales]

http://www.ielogical.com/audio.html#basement details some of my experience in setting up the Force sub.

Fine tuning the crossover frequencies patiently pays significant dividends.

I made a drawing of the level / frequency controls and made many copies so I could return to a starting point while experimenting.

[Mike Dzurko]

http://www.ielogical.com/audio.html#basement details some of my experience in setting up the Force sub.

Fine tuning the crossover frequencies patiently pays significant dividends.

I made a drawing of the level / frequency controls and made many copies so I could return to a starting point while experimenting.

Excellent and thought provoking read. I hope EVERYBODY takes the time to read it. Thanks for posting!