Despite what you would gather from looking at a mess of wires, carpet, and MDF in the back of a Honda Civic hatchback, building speaker enclosures is a pretty complex business. To get the right frequency response, you’ll need to take into account the driver’s resonant frequency, the volume of any internal components, and how well the speaker works when it reaches the resonant frequency. Heady stuff, but when [Rich] at NothingLabs started 3D printing his own speaker enclosures, he realized he could calculate an ideal enclosure automatically. Ah, the joys of OpenSCAD.
[Rich] wrote a bit of OpenSCAD and put it up on the Thingiverse Customizer, allowing anyone to manually enter a box volume, height and width ratio, size for a speaker hole, and even bass ports.
There are a few really cool features for this way of constructing speaker enclosures; assembly is a snap, and it’s most likely air tight right out of the printer. [Rich] printed an enclosure for a 3″ driver that has a frequency response down to 66Hz – an extremely impressive piece of work. Video below.
Very cool! The only thing that I think is missing, just based on some of my experimentation with alternative speaker enclosures, would be some provision to make the walls stiffer. The really awesome thing with 3D printing is that you could have features printed right in there to allow the walls to be supported at a regular spacing. This is really hard to do when you are building speaker enclosures out of wood, but all of the best manufacturers do it.
Just a possible future improvement to what’s an awesome project! I’m always looking for reasons to use a 3D printer, and this looks like a good one
I would not expect it to be airtight straight off the printer. Not at the instantaneous pressures required for subwoofers, anyway. I think pressure leak is going to weaken the sweet spot in the speaker.
My idea for an upgrade: Just calculate and print the enclosure, then make a good wooden or injection-molded copy of the 3d print.
When I built my own subwoofer enclosure it really wasn’t too bad. The calculations have to be done right, which means getting a good approximate of the average interior volume of the speaker, and subtracting it from the sum of the box’ internals with the round hole depending on how you mount the speaker.
Love it; let’s mature it some more!
I’d be surprised if it wasn’t airtight, assuming a single part… which this isn’t…
Good thing hackaday did a piece on something that would do it!
http://hackaday.com/2013/02/26/giving-3d-printed-parts-a-shiny-smooth-finish/
Also, it’s a funny thought, making the model, printing it, and then copying it out of wood…
Great! I hated to assemble those msg parts for a sub.
Now i could just print them… oh wait, who possibly print me something that has 60 Liter?
Anyway, let me check this OpenSCAD
In the old days…like up to 20 years ago, we always used the word “parametricized”!!
Damn young 3D printing whippersnappers!!! Math technical terms are SUPPOSED to be hard to spell /snark
Very cool, but I don’t think I would have 3D printed it. I mean, 11 lbs of filament?! I think his lasercut method would be much quicker and cheaper. The script on the other hand must be quite useful.
Finally! 3D printer used for something hard to make classic way. Im pretty amazing when someone print cube with six sides. When is on market for less than 2€… Just because they have 3D printer.
Could be some much better I think:
-Internal reinforcements
-Nice internal shape
Agreed. Also I wouldn’t want my 3d printed version to go into the wild when it could be copied in a better material.
For such simple box it’s overkill, but for some complex box it would be useful.
Neat application for 3d printing, not necessarily the most practical, but interesting none the less. I would worry about stiffness, especially if you tried to go larger. If you really want to get serious, this tool called Speaker workshop has been available for some time, and has TONS of features useful for doing this. If you are into building speakers, you should really check it out:
http://www.speakerworkshop.com/
Sadly it is kind of old, but I have used it to build several boxes, subwoofer and three way full range, and it has always worked great. Couple it with a nice parametric CAD program like Solidworks or something similar, add in some quality materials and workmanship, and you can build some really nice stuff. The software linked above does ALL the calculations you need, ports, volumes, resonance testing, speaker testing, everything.
What would make it extra nifty is the ability to design and print optimized enclosures to fit into odd shaped spaces and to take such an odd shaped enclosure and determine what sort of speaker would work best in it.
Given the nature of filament, cooling, bonding, etc… I’d expect a large number of resonant nodes inherent to the structure unless you were to make the wall thickness significantly thicker than any of the traditional materials. From what I’ve seen/handled/touched of 3D printed items, at least, you might want to consider printing the walls in some manner of hollow construction, then filling them with sand to overcome the properties of the plastic and allow for reasonable sound dampening. It will be interesting to see if anything comes of this in the high-end of the audio world (desktop cubes are one thing, no one has any reasonable expectation of quality there; but more traditional speaker applications don’t suffer low quality output gladly).
Fascinating.
“…a mess of wires, carpet, and MDF in the back of a Honda Civic hatchback, building speaker enclosures is a pretty complex business. To get the right frequency response, you’ll need to take into account the driver’s resonant frequency…”
Cracked me up! :-)
Great piece of work. I had a friend that was working with speaker design and saw him wrestling with the maths and trying to fabricate with wood and NC machines. 3d Printers with integrated CAD along with optimisations for resonance etc will impact here for sure.