95Honda

Read Martin King's white paper like Sean said, will help a lot...

Are they close to original softparts? If so I have the T/S at home on BBPro6... I can look when I get back this weekend, I am in Springfield Ohio working right now...

I would search the forum first to see if you design goals are being met.

The best advice is to model your chosen driver in your chosen alignment. If you want to do a bandpass, model it. And by modeling, that means modeling, not picking a "ratio" arbitrarily or random tunings. Look at the response plots, driver excursion, port velocity and impedance plots. This will be the #1 source of information to make your decision. There are a lot of down sides to a bandpass which become apparent when you start modeling, and the vent arrangement is a huge one (note how I said you must look at vent velocity)... Just be prepared to NOT make design compromises purely for the sake of sticking with a bandpass, that will ultimately kill your results...

I think the problem is people come here looking for simple solutions to complex design/building/evaluation scenarios. If you want it to be easy and not involve math pay someone to do it. If you want the best possible outcome, as with anything in life, be prepared to do the work...

I would study up on algebra a little for your area calculations. I would also do some reading on a 4th order bandpass. Your situation could be an appropriate situation for one, but you really need to do your homework and/or get someone who knows what they are doing (the "ratio" and the manufacturer suggested sealed and vented sizes have NOTHING at all to do with a bandpass) to help design/build your enclosure.

I was designed to slide right under a stage and fire out towards the crowd...

I have built a lot of 4th order bandpass enclosures, and a few 6th order bandpass alignments, also... I used this design successfully in the late 80's early 90's with the drivers available at the time that had low Xmax, big Vas and mid Qts... They worked well because the bandpass efficiency really helped the low displacement drivers on the bottom end and their large Vas made enclosure design easy due to large volumes that lent to easy vent construction. I built a lot more of these for home audio than car audio. Nowadays, drivers have much more linear excursion and efficiency than comparable drivers 20 years ago, so I haven't really seen the advantage. The last one I built was a pro-audio sub with a pair of Eminence 12" drivers that were perfectly suited for the alignment. But again, I had specific criteria to do this... I also had a carefully designed passive crossover that really helped it work right...

I think you are missing where modeling will help you. It WILL tell you exactly what you will hear. This is what I mean: Take the last enclosure you built and really liked the way it sounded. Model it. Make note of the response. Now, when you model the next enclosure you target the response of the one you built that sounded so good to you and you will be way ahead of the game. No constant rebuilding. There are certain responses people like to hear, with modeling, you can objectively repeat the desired results with little wasted time, money and materials...

If the amp is broke, then yes, I would replace. I installed an BC3500 last year. It is ton of power and a HUGE amp. It works fine.

If an amplifier is rated into a sine wave (they are) and the power supply can keep, they can produce much more power producing different waveforms. They can produce up to 2x the sine wave rated power into a pure square wave (this rarely happens, but you can get close to it if you are really giving it hell). If your alignment requires more than your current 1200 watts to reach full linear output (assuming the amp isn't damaged or you have a setting somewhere else in the signal chain wrong) then more power may help. It sounds like something else it wrong, though. I would just double/triple check before spending money on another amp... Also, 1200 watts continuously will make ANY woofer warm...

If your headunit puts out that much voltage you can clip just about any amp regardless of gain setting. Are you reading RMS/Average with your scope or Peak-Peak? The gain settings are rating in RMS... If you are reading Peak-Peak, the RMS is less than half of that value. That unit has an adjustable sub output, right? If so, all of the amp gain problems are a non issue... You might already be at the output capabilities of the sub depending on your enclosure, and more power could make things worse. BTW, your 1200 watt amp could be possibly creating 2400 watts under the conditions you are describing, that could easily cook you Fi Q!

Ha rental! Game on, your leaving it someday lol! Best place to learn by mistake....

Just need to plan out how to get the woofer mounted IB and if you do a manifold keep the resonance an octave or so above your highest frequency. And honestly, you can use any driver for IB, you just may have to add some EQ to ones that have a real low Qts... And 18s tend to have enough displacement that they will work no matter what, lol...

Lol, it is easy stuff, really... I just wish I had a decent room... Maybe MKII will be when I finish the basement this year... Concrete walls... But in all honesty, for a living room system upstairs that has a good (and almost invisible) 5.1 system and a 65" LED screen, I couldn't ask for more...

Lol... I wish I had a better room, our living room is probably the worst room I have ever attempted a full-out sub-stage in... Thank god for enough output to overcome some of the room problems...

Watching "Derek Trucks Live" on the Pioneer Elite Blu Ray through the system... Sounds awesome... The IB has such flat response it blends well... I am liking this setup... http://en.wikipedia.org/wiki/Songlines_Live#mediaviewer/File:SonglinesLive.jpg

All the HVAC is done, everything is heated/AC'd in basement... I just have to finish wiring and plumbing then drywall... The Soffit is for looks, it will be open all around the subwoofer and the utility room... No worries!

So we watched our first movie tonight... It literally moves the floor... Now everything rattles so much on quiet scenes that just have sub sonics that it is annoying... So I am going to start chasing down rattles... We have a crap load of stuff in the living room, so I think it is time for a test tone CD and a lot of time...

Power handling has nothing to do with output, at all.

No blackout, you can't see anything, it matches all the other vents... To give you guys an idea of how efficient the sub stage is, unless I have the gains on the sub amps at 1/4 or less, the receiver sets the subwoofer to maximum attenuation during the auto calibration with the microphone, lol... I did have one problem I had to sort out, there was some noticeable 60Hz hum caused by a ground loop, and the fact that none of the Pioneer gear is grounded, lol... I ran a #8 ground wire to bond the receiver and sub amps downstairs, zero hum now!

I haven't modeled, but that sounds big enough... I have installed a few of those exact drivers...

All done! Bass is amazing, zero peaks/dips, just solid low end. It turned out more efficient than I thought it would be. With drivers mover a millimeter or two maximum, the output levels are shaking the walls upstairs. No vent noise/chuffing that was obvious. I did run a flush cut trim bit on both ends of the feed to the vent so there aren't any mismatched wood joints... The surrounds sit about 1" behind where the finished drywall will hang, so between that and the 3/4" for the grill frame clearance will be perfect... The grill will be 36" x 60" and will be stretched with white acoustic cloth... I always liked IB, it has just been forever since I have been able to enjoy it. Everything turned out great, I wouldn't change a thing...

I have hung on to the XXXs for almost 10 years. They are still in perfect shape and have been waiting for something like this... Their Qts is really too high for vented alignments, so sealed or IB is the goign to be the trick...

Manifold all done. It was a bitch getting it up there myself! I'll mount the woofers Sunday, I want the glue to cure all night. Hurricane nuts and 10-24 allen head cap screws to secure the drivers...