View Full Version : What filter slope, type and frequency for your subwoffers and why?

10-26-2010, 12:26 AM
Dear all,

I'm using two JBL SUB1500 in separate closed cabinets as subswoffers in my 5.1 system. They are placed right rear in the room and I'm using a digital x-over.

I would really appreciate some input on how you hook up you subwoofers to your systems. I understand that this may differ from system to system and room to room but maybe there is some basic ideas/trends to add to my thinking.

What slope do you use (6db, 12db....48db)?
What type of filters (analog, digital, Butterworth, Linkwitz-Riley, Bessel) do you use?
What frequency do you use? Different for movie and music?
Do you have the same x-over point in sub x-over and main system or do you do overlap?

-Grateful for you input

10-27-2010, 01:31 PM
No one using subwoofers?? :blink:


louped garouv
10-27-2010, 01:43 PM
No one using subwoofers?? :blink:


i use a "DJ Crossover" from a company called "sound environments" in NJ


10-27-2010, 01:48 PM
I would use a Crown XTi. Choose model with enough power.

Then use the built inn crossover. 24 or 48dB linkwitz.

10-27-2010, 08:24 PM
Hello Rob

I am using 24db L/R on my LE-14A L+R subs at 50Hz. These crossover to E-145's in 5 cubic ft boxes. I chose 50hz for 2 reasons I get good integration with the E-145's and 50 Hz is the where the displacement peak is for the LE-14's in my boxes. With the 6db down point at the crossover frequency I only get 1/4 the power there so it helps limit the excursion at the peak displacement. Works great I have never had the old boys bottom out.

I use the THX 80Hz crossover point on my LFE B380 which is about to get a brother. That will give me a pair for a bit more headroom for the more demanding sound tracks. I typically don't hit the mass rings but it's real close so I want more safety margin down there.


10-28-2010, 05:25 AM
My sub1500's are crossed at 50 hz 24 db L/R. Using an Ashley Parametric (about a 4db boost at 20hz 2.2 cuft sealed enc) and a Rane E/C. Powered by a Crown K2.
I run my mains at full freq in the theater.

This is just what I have found works well in my room. Anything higher you start to really hear the subs taking over!!