I think I'll likely just do a sealed box with some cheap plywood, and stuff the daylights out of it. Two drivers in a common box, facing out of either end, approximately 80L (based on the earlier recommendation of 30-80L)or so volume, and stuff the daylights out of it. Simple single internal brace. Sound good and simple? should be a $20 box, simple build. Round up all the measurements to nice even numbers for easy cutting and math.
Think about bracing in all 3 dimensions -- don't need much but buys you a LOT of stiffness per volume/weight.
I would measure at least the resonance frequency before building anything. I wouldn't be the least bit surprised if the actual resonance frequency turns out to be much higher than the datasheet specification.
Sometimes really nice drivers at budget prices show up as Parts Express buyouts. But sometimes, a low price buyout is just a cheap-n-nasty driver.
This appears to be one of those latter times. Notice the low sensitivity, the high Qts, the small Xmax, the huge disparity between the advertised power handling and the actual power handling limits by Xmax. All of this screams "The magnet is cheap and much too weak to control the coil!" , "The voice coil is too short for a woofer!" and "The red cone is our selling point, not the performance!"
Basically, this speaker was designed to provide the mating call of the poorly educated urban teenage male with an old lowered Honda with a 4" exhaust tip: "Thumpa! Thumpa! Rattle! Boom!"
In the small interior air-volume of a 1992 Honda hatchback, a 10" speaker can make fairly loud thumping noises even with a limited Xmax. Especially if the resonance frequency is pushed up to about 70 - 80 Hz by installing the woofer in a tiny sealed carpeted particle-board box bought at the local Chief Auto Parts for $29.99. Who cares if Qts is now raised to 2.5? It will still boom, won't it?
With the manufacturer's evident lack of concern about quality, chances are the actual Thiele-Small parameters won't match the ones on the data sheet. And that will mean all your hard work (and money) spent on building a carefully tuned enclosure might be wasted.
The good news is the speaker was only $10, so you have very little to lose.
If I were in your shoes, I would go to the nearest construction site and ask the foreman if I could raid the dumpster for either a large sheet of rigid foam insulation, or a sheet of old plywood. Cut an 8" hole in the middle, mount the woofer behind it (mounting to foam requires a minimal plywood plate to spread the weight), stick it in a corner of the garage, enjoy!
Thumpa, thumpa, boom!
-Gnobuddy
Yes, but break them in first.
Resonance frequency is likely to shift downwards until they settle in.
Agreed. This is one of the very few cases in audio where "breaking in" actually does something real.
The kindest way to break in a woofer is to provoke substantial cone excursion (to exercise the stiff new spider and surround), without generating a lot of heat in the voice coil.
This means driving the (unmounted) speaker with a sine wave at a frequency below it's fundamental resonance frequency. It won't take much power to create a reasonable amount of cone excursion at these low frequencies. Don't turn up the excursion beyond the driver's capabilities - 3 mm should be plenty, verified by holding a Q-tip 3 mm from the cone and turning on the drive signal.
If lacking a signal generator, a low-voltage 60 Hz transformer and a rheostat can be used in a pinch. But 60 Hz is above the manufacturers claimed f0, so not ideal in this case.
But all these niceties are, well, too nice for this particular speaker. It's a cheap and cheerful thumper, I wouldn't bother building or measuring anything, just mount it in a big baffle and let it do it's thing.
Someone mentioned a transmission line (a higher Qts means less stuffing needed in a TL.) One relatively cheap and easy (and also bulky and ugly) way to go that route is to get a couple of 10" cardboard tubes used for casting concrete columns ( Quikrete 10 in. x 48 in. Building Form Tube-692202 - The Home Depot ).
A quarter wavelength at 34 Hz is 2.5 metres or 8' 2.5". Two of those 48 inch Quikcrete tubes taped end to end should be a good starting point. For garage use only, based on sheer ugliness. 🙂
But even the cheap TL involves 20 bucks worth of cardboard tubes...for a $10 speaker of dubious quality. Nah, stick with my original idea, dumpster-diving for a large piece of rigid foam insulation or plywood!
-Gnobuddy
You could use the tubes sealed. Hopefully the generic foam surround with the generic cone will result in a sub-40 actual fs.
Thanks gnobuddy.
Maybe a pair of leftover plywood sheets hanging from the rafters in the garage (they're bare frame, no ceiling) and a couple full rangers would be a quick cheap way to go.
Maybe a pair of leftover plywood sheets hanging from the rafters in the garage (they're bare frame, no ceiling) and a couple full rangers would be a quick cheap way to go.
You already have these, so it's sell'em, or my preference "have fun with'em.
My vote is now on the isobaric sealed box arrangement. Simple, easy to make box with 2 chambers and a single "screw on" lid to covering both chambers. The driver iso chamber is small <10L and the larger chamber is 40L filled (use rags if no FG is available). Drivers wired in series to make them easier to drive.
If you don't like the sound, then it can become an experiment with EQ possibilities or xmax and power handling. 🙂
My vote is now on the isobaric sealed box arrangement. Simple, easy to make box with 2 chambers and a single "screw on" lid to covering both chambers. The driver iso chamber is small <10L and the larger chamber is 40L filled (use rags if no FG is available). Drivers wired in series to make them easier to drive.
If you don't like the sound, then it can become an experiment with EQ possibilities or xmax and power handling. 🙂
I have a weakness for cheap speakers too, but building a box for this one seems like far too much work for far too little return. "Putting lipstick on a pig", as one of my salt-of-the-earth buddies would have put it. 🙂
My most recently acquired cheap speaker is a loaf-of-bread sized Digital Research thingy, with a pair of roughly 4" aluminium-cone speakers and a tweeter in a D'Appolito (aka MTM) layout. It cost a whopping $5 at a local thrift store, and last night I found out that it makes a quite passable small guitar amp when connected to a cheap class-D power amp board with a Danelectro Fab chorus as a preamp.
I might hook up a 20-volt cordless tool battery and package the lot up as a grab-n-go portable guitar amp.
Never heard of Digital Research? Do an Internet search for "white van speaker scam", and you'll quickly learn more about the antecedents of this, err, world-famous luxury brand. 😀
Wikipedia even has an article on the "white van speaker scam": White van speaker scam - Wikipedia
-Gnobuddy
Attachments
Five dollars. And it works. Everything I have (mostly) came from a thrift store or garage sale, so yeah: that's a pretty pig!
It sounds surprisingly good with my beater Epiphone guitar, too. I was expecting harsh and nasty, but no, it sounds good.
And a pretty shade of lipstick, too!
-Gnobuddy
"The speaker scam was common in the 1980s and is believed to be the origin of the use of the term "high-end"."
So that's where all the snake oil comes from? Did not know that. :-D
I am also in favor of not wasting material. OB, slot loaded or not still gets my vote.
Titan's T/S
Hi there: I purchased 4 of the red frame 15-inch Titans and currently experimenting with OB's. I ran the T/S on them and found 2 to be almost identical and the other 2 to be within 5% of the PE published spec's, rather good for any commercial diver. Have fun and enjoy, hope you post your listening comments... regards, Michael
Hi there: I purchased 4 of the red frame 15-inch Titans and currently experimenting with OB's. I ran the T/S on them and found 2 to be almost identical and the other 2 to be within 5% of the PE published spec's, rather good for any commercial diver. Have fun and enjoy, hope you post your listening comments... regards, Michael
I had considered 20 for install in my minivan for ***** and giggles.
Bjorno...you must love Hornresp.
Bjorno...you must love Hornresp.
I'm strongly considering grabbing a few more to make some ceiling arrays for the garage, but have toyed with the idea of using them in my car... Two 10" woofers crossed at ~300 hz or so should be plenty of low frequency support in a 73 Super Beetle 🙂
There's a memory brought back, when I had a car stereo shop and did stuff like mount woofers in VW (front) trunks firing into the foot well (?). Those drivers were no better than these and yes bass in the cabin was the result. When the owner hacked off the roof they were no longer sufficient...
I think that's coming close to the intended application for these woofers.
I don't suppose you happen to have a lowered flat-black 1992 Honda Civic hatchback with a 4" chrome exhaust tip? 😀
-Gnobuddy
Do four - two in the well behind the back seat and another pair up front. You have all that four cylinder noise to deal with, right? Displacement! Cheap power!! Turn it up!!!
😀
You just described half of the car clubs out here. 🙄
Heh. I'm not sure I would get that crazy. I put 500~600 miles on my Super every week. If I replace the stuff I've got in there now its going to be for Faital Pro or something comparable. I'm currently running two 6.5" pioneer coax each, front and rear. Single basic 8~10" (I forget which) powered sub by I think JBL. Total budget setup. Rear I have plenty of room for a nice rig if I make up a new rear shelf, front is way more limited, not many mounting locations other than the kick panels, which is far from an ideal location.
Maybe a pair of these titans in the rear shelf, with a pair of Faital Pro 3FE25-4 for the 300hz and up range would be a good setup? Hmmm. Could even make up a VW logo to cover up the Titan logo on the center of the cone 🙂
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