Underground sub DIY

[subharmonic]

Anyone got any ideas on materials and drivers to DIY one of these for a patio install job I am doing? I was thinking a Lab 12 and some 14" PVC pipe housing could do some damage for a lot cheaper. It needs to be a pipe port install given the necessary placement so horns are out.

http://www.nilesaudio.com/product.php?p ... ID=FG01668
or
http://www.techwarelabs.com/speakercraf ... er-ground/
or
http://newsite.bayaudio.com/outdoor

http://www.youtube.com/watch?v=3-_oKlDteDw

[biggerrigger]

You are off to a great start with your ideas. One thing to remember is that you can model subs that would have no use in a living room due to too long of a port but will do great buried in the yard.
I have done 2 builds/installs to date and both were sonotube based with the addition of PVC sewer tubes ports all wrapped in fiberglass to weatherproof. The difference in the designs that you linked to and mine were I used a 2"x15"x15" concrete paver stone as my lids and placed a large planted pot on one and a sandstone bolder on top of the other. With the other landscape in place you could not tell where it was located even if you looked real hard.
A word of caution before you install is to remember to use the proper gage wire from the amp to the sub as this can be quite a long run from the the amp in some situations.
Although I do not have any pics to contribute to your cause I would be more than happy to help with the design and construction ideas but not with the install. You are on your own with digging the hole.

[subharmonic]

PM to BR will be sent shortly as I don't want to get into box design in open forums.

I am being contracted in by my wife's cousin the landscaper artist, no hole digging for me or brick laying (read on). I mainly get the finish work.

What I am looking for here is what is going to take make these: waterproof, reliable, worth while (loud), reliable, good sounding, reliable and hidden. Looking to fill 80-40 cycles anything slower will be icing. Really just wanted to see what materials and drivers you guys recommend. Keeping in mind it gets to negative single digits a couple months out of the year with dips for days/weeks to -40 °F to -30 °F, so the deeper the better.

411:
The tops I am looking at are rated between 85-91 db with 3db downturn at 80-90 hz depending on the particular one I choose. We have tight space constraints because of 2 of the 4 are being built into a massive fireplace he will cut the brick around them, actually going into the brick. The listener will be about 30ft in front of the subs to 30ft behind them so I need some power to catch up. It is a rural lot and a young party girl with money so loud trumps SQ.

[CoronaOperator]

It is a rural lot and a young party girl with money so loud trumps SQ.

pics and relationship status of said girl?

[subharmonic]

It is a rural lot and a young party girl with money so loud trumps SQ.

pics and relationship status of said girl?

Haven't met her yet....if she is like the normal party girls in this area I wouldn't touch her even with yours.

[sine143]

grab win isd. design a sixth order BP box around you driver of choice. Six inch pvc should line up to the 5.5 port sizing. Hell, theres even a forum member here that has some MCM 12s available (modelled kind of nicely in ported configuration). you could probably throw those in a huge Duratexed box and bury it no problem.

[subharmonic]

grab win isd. design a sixth order BP box around you driver of choice. Six inch pvc should line up to the 5.5 port sizing. Hell, theres even a forum member here that has some MCM 12s available (modelled kind of nicely in ported configuration). you could probably throw those in a huge Duratexed box and bury it no problem.

The things that worry me about this plan is the cones are treated paper (basket is aluminum so thats good) and the when (not if) moisture gets in the box it most likely isn't coming out , ever. So how would the cone handle a little water or a wooden box even if it is Duratexed. Of course those MCMs means 2 drivers so if one fails it isn't the end of the world.

[sine143]

my b, you want a 4th order bandpass (sealed rear chamber, ported front chamber, with the bell cover on top of the port. ). if you want find something cheap that has a more suitable cone material, there are many auto drivers

[biggerrigger]

My two builds both used the Eclipse 8812-4 and 8810-4 drivers. Both use a aluminum cone and basket and a very heavy rubber surround.

If these drivers can withstand multiple trips to the mudpit in the open back of my 89 Blazer they will withstand anything. We would go out to the pits all day long and literally have hundreds of pounds of wet sticky mud covering every inch of the truck and the fiberglass box in the back of the Blazer. When we were done muddin we would blast off the worst of the mess with the 2" hose at the mudpit and make way to the carwash to get it clean. The truck,box,and cones routinely got power washed and I never had any issues with mud or water damage.

I should mention that I did have a matching set of SS beadlocks laser cut (that matched the ones on the tires) to clamp the drivers into the fiberglass box and I believe that they were the reason that I never had any problems. If this is not done you will have a failure down the line due to cone/surround separation. I did the same in my underground boxes but used a old plastic cutting board to make my hold down rings as they did not need to be pretty they just needed to be functional because no one could see them.

You need to keep in consideration that we are not working in a normal environment when underground. You have a constant temperature of 55 degrees(in most parts of the country) and high moisture. If you want your build to last you have to take all of your environmental considerations into account and chose your construction materials and water proofing techniques very carefully.

If you get any water into the system you will no longer have a great sounding underground sub but you will instead have a great habitat for frogs and salamanders.