Found a great 15" Driver for IB

[hulkss]

I have four dual opposing Infinite Baffle (IB) cabinets arranged along the front wall of my home theater (the black cubes in the photo below).  The house has a crawl space under it. The back volume of the cabinets is open to the crawl space. This was a very easy build of four small cabinets (photos below). The dual opposing configuration cancels the acceleration force reactions of the heavy speaker cones to prevent vibration.

The drivers are exposed to humidity from the crawl space so I used eight model V154DV2 automotive subwoofers from Cerwin Vega. They have excellent high durability Santoprene Surrounds and Parabolic One Piece Stamped Carbon Fiber Poly Cones. They appear well constructed to take a lot of abuse. You can buy them from Cerwin Vega directly. Their specs are perfect for IB applications. A 1000 watt amp on each cabinet is enough to get your attention. The floor tile in the photos are 18 inches square.

Nominal Subwoofer Size 15”
Nominal Impedance (ohms) 4Ω
SPL (db) 86.7
Re (Ω)[series] 4.0 / 4.0
Qms 9.5
Qes 0.74
Qts 0.69
Fs-Free Air Resonance (Hz) 22.1
Vas (Liter) 166.8
Sd (cm²) 0.08
BL (T*M) 18.5
Xmax - Inch(mm) 18.1
Cms (mm/N) 0.32
Mms (g) 255.2
Pwr (W) NOM/MAX 550/1500
Total Diameter 15.78” (401mm)
Mounting Diameter (inch/mm) 13.62”(346mm)
Screw Hole Diameter 0.82” (21mm)
Mounting Depth 7.28”(185mm)
Magnet Diameter (E) 7.08" (180mm)
Displacement (ft3/L) (0.15ft3 / 4.18L)

Below (bottom) is a REW frequency sweep measurement in my home theater seats using a high quality calibrated measurement mic and preamplifier. The crossover to my main speakers was set at 100 Hz for this measurement.

[dan77]

Sure looks good! Must be fun! Interesting that you went with ‘innies’ rather than ‘outies’.

[hulkss]

Dec 5, 2023 9:14:15 GMT -7 dan77 said:

Sure looks good! Must be fun! Interesting that you went with ‘innies’ rather than ‘outies’.

You want to be hearing the front cone side of the driver. The motor side can generate air pumping noise from the motor air vents and cone suspension spiders.

[dan77]

My outies are installed in such a fashion that the front of the cone does face the home theater.
The back of the sub speaker faces the space below my HT.
But I think your setup looks good.

Here is my manifold with the front of the sub facing the home theater

[FOH]

Always thought "innies" and "outies" referred to the manifold sex, from the floor's perspective.

ie., ... if the manifold protruded out into the room, ... it's an "outie", oftentimes the exception.

Whereas typically many manifolds are oriented as an "innie", ie., into the floor/wall/or attic.

Doesn't really matter, either way.