Space limited... 8" wedge sub behind TV... advice?

I did some modeling of the subs. The problem with the 240watt plate amp is it has a rumble filter at 18 hz and both subs will bottom out below 22 hz. If you were to use the Bash 300 amp, the rumble filter can be changed to 25 hz and both subs would be protected. The Dayton is a 4 ohm sub and the CSS is a 8 ohm sub. The Dayton will take 80 watts to reach Xmax. The TRIO 8 will take 150 watts to reach Xmax and has much more output.

The following is only if you want to build a 'premium' level of subwoofer with outstanding performance.

If you really want the most output from a tiny sub, are willing to spend more, will use a little bit bigger box(to accommodate the slot port) and want another level of performance, it will be difficult to impossible to beat the JL W7 8". In 1 cubic foot + appropriate folded slot port of 7" wide x 2" high x 44" long. Combine with O Audio 500 Watt BASH amplifier. A weaker amp is not recommend for this driver. Also, the subsonic filter is important on the O Audio for the safety of any ported sub used for HT purposes. You will achieve ground plane 2 M output, realistically, around 105dB at 28Hz, 107db by 40Hz. This is accounting for some thermal compression and port compression. The modeled SPL is actually quite a bit more, but I try to give more realistic performance numbers based on real world factors. Realize, the W7 will have less thermal compression and more linear excursion when compared to most anything else. I tried to select the smallest possible port for compact size, and some compression is occurring as a result.

BTW, the factory specs for 8W7 are way off on VAS. I have tested 2 different pairs from two different production runs and they are consistent, both with VAS nearly 1/2 of what factory spec indicates.

The 8W7 is about $250 from online discount sellers. The only comparable 8" I know of is the now unavailable TC Sounds built one sold by Sound Splinter. However, as was said earlier, it may not be suited to such a small volume. The driver can safely operate at high SPL to about 20Hz in a 1.5 volume ported cabinet! It is a rather amazing 8" driver with extreme thermal capability and incredible linear excursion. I can say that in my use in sealed applications, the one way 19mm xmax is a conservative rating I suspect. Photo of 8W7 from rear.

Here are the actual T/S parameters measured from an 8W7 for modeling purposes:
Qms: 7.765
Qes: 0.734
VAS: 0.326 ft^3
Re: 2.78
Le: 1.34 mH
BL: 10.39
Xmax: 19 mm
Pe: 500 W

I'm getting different port lengths then you are. A 3 inch port would be 22 inches long and two 2 inch ports would be 20 inches long. Both WinISD and the P.S.P. port length calculator say the same thing.

http://www.psp-inc.com/

Also, changing the high pass filter to 25 hz involves changing 2 resistors on the amp board.(R26 and R25) If you're not comfortable doing this you'll have to find someone who is.

Update... like all good ideas, success lies in the execution. After spending much time modeling and researching, it made zero financial sense to make myself a sub. I searched Craigslist and eBay for a few weeks and ended up buying an entire Energy Take-5 Classic 5.1 w/brackets for $100 a used 8" Mirage sub for $40 and tried out both subs in the space behind the TV. Both fit perfectly, and I could get the TV stand as far back as I needed it to go and the subs both fit like gloves.

I couldn't be happier with the results... and although I don't have the talking points I would with a 10" custom sitting back there all stealth and rocking the whole house, I have no regrets. My next house (Navy moves me every 2-3 years) will have a dedicated HTR so I can get back into the hobby and I WILL GO ******** HUGE! I'm set for now though.

The picture is of the original test fitting... that mess of wires no longer exists (yup, just my ego reassuring you guys I'm no slob).