Two 10"inch and two 12" inch subwoofers and what to do??

[richie00boy]

Have you checked the frequency response of the LFE output? They usually start rolling off around 80Hz and is a mono channel. If you have very small main speakers this could produce a hole in the range.

 

[Moondog55]

Can you provide some information about the bookshelf spekers?? and perhaps check the receiver settings, I think richie00boy may be right and the subbies will only be getting LFE output, as I said earlier I would not use those drivers over 120Hz myself.
Perhaps the problem is not with the LF but with the settings on the receiver or the fact that the small boxes naturally roll-off to soon, leaving that "hole" in the response

 

[Gentle1Man]

Even when I had a pair of Infinity Reference Six speakers with the ten inch KAPPA woofers they lacked upper bass crossed over at 200 hz. The foam went out on the stock tens and I replaced them with some Kenwood ten inch woofers ((((Size 10 -inch
Impedance 4 ohms
Cone Material Pearl Mica IMPP
Surround Material Urethane Foam
Sealed Box Volume (cubic feet) 0.8 - 1.25
Ported Box Volume (cubic feet) 0.8 - 1.5
Port diameter (inches) 3
Port length (inches) 5
Free-Air No
Dual Voice Coil No
Sensitivity 91dB
Frequency Response 28 - 800 Hz
RMS Power Range (Watts) 35-130
Peak Power Handling (Watts) 500
Top Mount Depth (inches) 4 1/2
Bottom Mount Depth (inches) 5
Cutout Diameter or Length (inches) 9 1/4
Vas (liters) 41.7
Fs (Hz) 35
Qts 0.83
Xmax (millimeters) 12
Parts Warranty 1 YEAR
Labor Warranty 1 YEAR ))))

The Kenwoods sounded great as replacements, so when I ran across the Kappa's on sale I bought a pair and replaced the Kenwoods in the Infinity Reference Six Speakers. When I did this I noticed certain songs did not have the midbass or upper bass sound that the speakers used to. So I think you can tell when these speakers are crossed over higher than they are supposed to. I have replaced my Infinity speakers with Athena

LS-100 Bookshelf Speakers
Design 5 1/2" 2-Way Curved Cabinet
Shielded Bookshelf Speaker
Power Handling 120 Watt
Woofer 5 1/2" Composite Fiberglas™ Cone
Tweeter 1" Aluminum Dome
Accessories -
Frequency Response 55Hz - 20kHz
Typical Room Sensitivity 87dB
Dimension HxDxW (in.) 12.8 x 9.7 x 7
Dimension HxDxW (cm) 32.5 x 24.5 x 18
Weight 1 Unit/Carton (lbs) 9.9/23.1
Weight 1 Unit/Carton (kgs) 4.5/10.5
Finish Black Ash ...

I found them on sale really cheap and thought I would try them. They sound better than I thought they would.

So does anyone have any suggestions on new 15 inch speakers or should I stay with what I have????

 

[Gentle1Man]

What is the difference between car & home subwoofer speakers???

What is the difference between car and subwoofer subwoofers. I know the sensitivity is rated different can they be compared or not even close??????? What stats would be the same????

 

[Moondog55]

Basically ( I may be wrong here) car subwoofers are designed to utilize the pressurization of the lossy space they are used in to give deep bass, this gives rise to what is can only be desrcibed as one note bass when heard from outside the listening environment, it is why some CD's are mixed overly bright as bass boost predominates.
You can get as much as 12dB boost at 20Hz ( even more if you drive a Datsun 120Y ) and a lot of car subbies have a sharp rising high end, add that to the resonance of metal cones and possibility of audible cone break-up noises at highish SPL and you need to be aware of the need to use them as designed ie; crossed low so the bad noise is cut out.
My general rule of thumb; sub-woofers work and are used to boost low bass below 80hz, woofers however can be used up to the cross-over to the midrange drivers.
I am using cheap 15 inch MTX drivers first order at 90hz in a 3.5 way but the 8inch woofers cross to the 4inch mids at 250, another cheap experiment.

 

[Moondog55]

I just found this article by the Briggs on the issue of using woofers with different resonances, interesting and I thought others might find it so.
http://members.myactv.net/~je245/obriggs.htm