The "insane stuff you'd love to build but never will" thread (1 Viewer)

[Bill Fagal]

Chip in with your own pipe dreams and let's hava little fun.
Project 1: Wall of sound
Step one:
Wall off the front third (or about 3000 cubic feet, which ever is greater) of your home theater with multiple layers of MDF, cross-brace it and seal it up. This is your enclosure.
Step two:
visit Orevox and place an order for enough DS-312 12" drivers to completely encrust your new wall. For example, if your wall is 16x8 ft. you'll snap up 128 of 'em. They're less than 9 bucks each, so quit whining. Sure their T/S params stink, but you're overcoming wimpy wimpy quality with hefty hefty quantity.
Step three:
Get busy with your router and circle jig, making homes for all 128 little air pumps. Weary not in well-doing.
Step four:
Mount drivers, wire them series/parallel, and connect them to a modest amp of 250 watts or so, downstream of a LT circuit to flatten the humpiness of the high-Q drivers.
Step five:
Stand back and survey the damage. For about $1200 in drivers, plus modest outlay for lumber, amp, LT circuit, and assorted sundries, you now have a subwoofer with the following characteristics:
A radiating surface equivalent to a single 9 1/2-foot driver that will displace over 2500 cubic inches of air at a mere 1/4" of p-p excursion. (Single-digit Hz? Yes--loudly.)
A baseline anechoic efficiency of over 107 dB/W.
A theoretical anechoic 131 dB at 250W (at which power level each driver will see just less than 2W.)
An eye-popping decor theme!

 

[Rory Buszka]

I want to build a multitude of 8th-order bandpass subwoofers and stuff them into the trunk of my car and use their huge efficiency + 1000 or so watts to win some SPL competitions

 

[Rory Buszka]

I can imagine a room with that subwoofer and a LT circuit that EQ's them down to 5 Hz. But you might want to take out your chair and install a toilet instead for those bowel-movement-inducing sounds.

If I built that room I would not allow people in that room, but I'd put in 2000w of power and use it to crush garbage.

 

[Cam S]

My dream, to have a pair of Avalon Sentinals that weigh in at 1000 pounds each, man are those things big and sexy! I also make a nice sub to fill out the lows using 4+ Uber subs, I think that would make some walls crack giving them 5000+ watts.

 

[Chris Tsutsui]

I'd build my subwoofer enclosure so that it IS my home theater. So that the entire room has subwoofers pumping sound outside of it to the "open world" and the rest of the bass goes inside the room. Then I'd have flared ports that lead outside for the HT to be tuned accordingly.

It'll be the first HT with chimneys designed as flared vents.

 

[Mark gas]

4 18 inch cervin vega strokers in 24 cubes tuned realy low like 22 hz powered by 4 big qsc amps.

Now somthing realy stupid

1 shocker audio 18 inch octo coil (yes thats 8 vc's!!Signature Series 18 with 8 Huge qsc amps (1 per vc) tuned really high like 60hz for some crazy spl.

 

[Griff]

Im seeing the JBL 2241H 18" HIGH-POWER LF DRIVER, 98dB efficient bass drivers, 4 of them a side. A few of the Bryston 4BST's, maybe channel per driver for the bass and mids JBL E120-8 12", and something class A 50 watts for the tweeters, which will be the JBL 2446H COMPRESSION DRIVER. Of course id be in jail for breaking many many laws, public and private nuisance, disturbing the peace etc, but for that one moment of earth shaking sound, i would be happy.

 

[Hank Frankenberg]

I want to build the best line array towers in the solar system. Despite several warnings about small full-range drivers, and doing ribbon mid-tweets with piston woofs, and spacing and crossovers and etc, etc, etc, I STILL want to build a line array that has the soundstage and transparency of Maggies, but with realistic dynamic impact.
Oh, I forgot: they must be very affordable (

 

[Bill Fagal]

Hey Hank,

That's something I'm hoping to try some day. A little over a year ago I picked up two cases of 32 PE 269-469 4" full-range drivers. Rememember those? PE was letting them go for under 70 cents each. I figure I can stack 24 per channel floor-to-ceiling in simple open baffles and have some fun. They'd be about 103 dB/w efficient, too. A little under 35 bucks for drivers doesn't exactly break my bank, either.

 

[Hank Frankenberg]

Bill, go for it! Possibilities include using only small full-range drivers stacked in a slim tower, a stack of small woofs 5" to 6.5" stacked next to a stack of tweets, stack of ribbons next to a stack of woofs, etc.
Have fun and good luck!

 

[Mark Seaton]

Hmm... this is tough because at some point I do intend to actually build up most of my ideas.
While Tom Danley does have the parts for a 3'x3' mouth Unity Summation Aperture loudspeaker, I really would love to make a 5' to 6' square horn and extend past the compression driver on the high end, and then drive the final LF section of the horn with multiple ServoDrive modules. Hhmmmm. The continuation of this is to put two of these in the front corners of a room where the walls of the room will effectively extend the horn. Then I want to use columns of in-wall subs to continue the horn loading (and resulting near zero phase angle) all the way down to the frequency where the cavity of the room begins to provide "cabin gain". You should be able to get sensitivity in the 106-110dB/1W(true 1W) range. On top of this you would have no reflections from the coupled walls, but only from the opposing walls.
The other intent is to achieve a 5:1 or 10:1 compression ratio in a true, low frequency bass horn where loading in the room is intended to provide the required mouth area, as the high compression ratio allows the length in more modest size. I'm thinking horn loading to 20-25Hz... Crazy stuff.
As I said above, none of this is out of the realm of possibility, THAT's the scarry part!
For the car audio nuts, we need to dig up the fan powered bass loudspeaker which Tom invented for the Sonic Boom simulator. It basically is a donut of airflow with a servomotor effectively modulating the airflow. 15 years ago it was able to generate ~2psi... I think we could do a little better now!
Regards, and fun dreaming...

 

[Rudy H]

A room that's 1foot think poured concrete, above ground.
Every possible square inch to be used up as a mounting place for uber15's playing as a sealed box (the room becomes the box ).
Each Uber15 with it's own K2 as well

 

[Bryan Michael]

here we go haha buld a seccond floor and put subs under each seat aka a 18 for each seat umbers buld a sub aray all the way around the room so ot would be a line all around the room with 10 inch drivers and a line aray too and a 200 inch screen that would be cool

 

[John A. Gordon]

Well, if it is a Pipe Dream, then my room would be a holodeck that will be whatever I want it to be when I want it. And if I don't like it, I simple say, computer, add ......

 

[Darren Mortensen]

Yup...I would have to follow up with John Gordon's HOLODECK and add my pipedream of making a PERFECT woman!

 

[Bill Fagal]

Just had a couple of ideas and thought I air 'em.

1: The false-floor bass horn.

Lay out a 2-dimensional horn on your subfloor with 2x4s on edge that runs 1x or 2x the length of your room and expands to a mouth the width of your end wall. Include 2x4 pieces within the horn expansion to allow you to cover the whole thing with more subflooring--glue and screw. Leave a 3.5" slit in the flooring along the wall for the horn mouth to open into the final expansion defined by the floor and walls. Cut a circular hole through the flooring at the horn throat and mount a driver in it with a back-chamber box over that.


2: The sort-of-in-wall cardioid bass line array.

I was just surfing through Meyersound's website and got interested in cardioid bass. Here's how you might do it in your home: take a dipole line array and remove the backwave. How? Start with a line array of opposed-force dipole woofers--like a stack of Linkwitz Phoenixes. Cut a hole in your wall approx. the width and height of the array and place the array perhaps 6" in front of it. While most of the backwave goes into the next room, sufficient will remain to give your bass good directionality. This alignment should be the last word on minimizing room interaction.

Bill

 

[Geno]

Easy one:
to own and live at the Skywalker Ranch
edit: Oh yeah, and I'd have HTF meets there every night

 

[Anthony_Gomez]

Something I WILL build, but at the moment it is insane with my current budget
3-way with the following drivers:
Raven R1
SS-12M/4631G00
SS-/8531G00
This will be a music only system.
Either ported, or a 4-way sealed with
SS-25W/8565-01

 

[Bill_Weinreich]

Fembot
Machine gun jubblies? How did I miss those Baby?

 

[Brian Bunge]

Tony,

Danny has a new speaker with a ribbon tweeter very similar to the Ravens. Damn, that thing sounds good!

Brian