3D Printed speakers - Unlock impossible designs compare to conventional

[somebodyelse]

A family of monitors using SB15, SB26 and augerpro waveguide, including measurements.
https://www.printables.com/model/661737-waveguided-bookshelf-speakers-using-sb15-woofer-an

 

[terryforsythe]

I am looking forward to finishing this project, this speaker will likely replace my Genelec G2s as desktop speakers.

If you are going to measure the speaker performance with REW, it would be great if you shared a harmonic distortion plot of the speakers. It will be interesting to see how well 3D printed cabinets perform in that regard.

 

[Keith_W]

Is it possible for DIY class 3d printers to use rigid enough materials for speakers?

I think I saw DIY Perks print a hollow shell and he filled it with concrete. Epoxy may be an alternative. I don't know

 

[DLS79]

I think I saw DIY Perks print a hollow shell and he filled it with concrete. Epoxy may be an alternative. I don't know

He has done a few if memory serves.

 

[Scgorg]

If you are going to measure the speaker performance with REW, it would be great if you shared a harmonic distortion plot of the speakers. It will be interesting to see how well 3D printed cabinets perform in that regard.

I will when I do proper measurements of the finished speaker. For crossover design measurements I didn't do absolute SPL measurements, just the same (low) voltage on both tweeter and woofer to get the relative sensitivities right. I can say that the woofer shows no odd behaviour above the noise floor of these measurements (~-45dB-50dB). Note that this particular speaker has fairly extensive bracing for such a small speaker, see image below:

 

[kemmler3D]

I haven't built any 3D printed speakers but I have thought about it a lot.

IMO Printing a speaker cabinet that can compete with 15-19mm of MDF is not very practical. You would have to do solid or nearly solid, very thick walls, which works against the strengths of the tool. It will be slow and ultimately kind of expensive, PLA / ABS are at least $10 per kilo.

This is not a knock on 3D printing... MDF just happens to be a really excellent material for speaker cabinets. Cheap, fairly inert, fairly stiff, fairly dense, fairly easy to work with... hard to beat.

However, I think making a hollow cabinet and filling it with sand and/or concrete could be really effective and pretty efficient, and would outclass MDF.

I am likewise excited by the possibilities for DIY. I think the title illustrates the most interesting thing about 3D printing. "Impossible" designs for conventional building techniques.

Most of the examples in this thread are possibly challenging, but by no means impossible to build conventionally. I want to see spheroid / teardrop shapes, multi-layer cabinet walls, things like that. Making 3 layers of sand, concrete, and sand inside a 3D printed housing is not really a big deal once you do the design. Not even remotely worth the effort for an MDF box, but if you're printing it, well, the construction is not the hard part. Even doing a CLD layer by filling it with green glue ... the hard part is pouring the glue.


Aside from that, Augerpro's work is really impressive and helpful to the scene and on DIYAudio you also have the user Patrickbateman who has done a lot of printed enclosures and other parts.


Post processing and finishing is a real job, but of course that's equally true of any wooden enclosure. For 3D prints I like to coat it with filler of some kind (wood, bondo, etc) then sand, paint, sand, paint until satisfactory results are achieved. Not difficult, just a little time-consuming.

Lastly, I don't really consider the size of the printer to be a true limitation, you just need a lot of patience and the willingness to glue several parts together.

(The current state of my 3D printed QRD project)

 

[somebodyelse]

Is it possible for DIY class 3d printers to use rigid enough materials for speakers?

HexiBase compared PLA with different fill densities with a few different wood varieties. 50% infill proved comparable to wood - not the best, not the worst.

Another option is a low density gyroid infill, then filling the space with sand, plaster, epoxy or similar.

Erin tested the little LCM a while back:
https://erinsaudiocorner.com/loudspeakers/lcm_nearfield_monitor/

 

[kemmler3D]

HexiBase compared PLA with different fill densities with a few different wood varieties. 50% infill proved comparable to wood - not the best, not the worst.

Another option is a low density gyroid infill, then filling the space with sand, plaster, epoxy or similar.

Erin tested the little LCM a while back:
https://erinsaudiocorner.com/loudspeakers/lcm_nearfield_monitor/

50% infill on a large print is a total drag, though. If I ever print any speaker housings I'm definitely going hollow and filling with something.

 

[somebodyelse]

50% infill on a large print is a total drag, though. If I ever print any speaker housings I'm definitely going hollow and filling with something.

Indeed - slow and expensive even with a reliable printer. The video does cover the long print times. I haven't looked for similar comparisons with different filling materials.

 

[DLS79]

Indeed - slow and expensive even with a reliable printer. The video does cover the long print times. I haven't looked for similar comparisons with different filling materials.

"Epoxy Granite" is a term you might want to look into, it's common in the DIY CNC world.

 

[dweeeeb2]

Just 3D print the mold for any material you want

 

[Glider95]

Thank you all for your enthusiasm.

I have updated the first post with the new links content given by your answers.

-------------------

"Epoxy Granite" is a term you might want to look into, it's common in the DIY CNC world.

Just 3D print the mold for any material you want

Personally, I agree that printing walls of 15mm or more does not make sense and the cost would increase pretty quick.

However, as shown in DIYPerks video, doing a shell and fill it with an a mix of plaster of paris as absorption material really does the job.
I can see some old discussions on speakers made of Epoxy Granite however nothing where it is combined with 3D printing. Maybe a new material to explore ?

 

[willi_vintage]

Prototype....

 

[willi_vintage]

I experimented a bit with modal analysis and came up with this design. What do you think? Cool or awful?

 

[Alexander Gödde]

 

[Rednaxela]

I experimented a bit with modal analysis and came up with this design. What do you think? Cool or awful?

Both!

 

[kemmler3D]

I experimented a bit with modal analysis and came up with this design. What do you think? Cool or awful?

Cool, but there's no reason the exterior wall needs to be the same shape as the interior wall.

I think having an irregularly shaped interior wall for the cabinet is an obvious move for 3D printing as you can scatter the internal waves and avoid any high frequency standing waves flat walls might give you. But you only need funky exterior walls if you like how they look.

 

[Ktacos]

Looks great but can't find the files anywhere.

 

[tktran303]

You need to go to and read part 2:

Files:

Make it Real | 3D Model Creation Platform by AnkerMake

Make it Real | 3D Model Creation Platform by AnkerMake Search, Create, Share and Print quality 3D models.

makeitreal.ankermake.com

 

[kemmler3D]

You need to go to and read part 2:

Files:

Make it Real | 3D Model Creation Platform by AnkerMake

Make it Real | 3D Model Creation Platform by AnkerMake Search, Create, Share and Print quality 3D models.

makeitreal.ankermake.com

These cabinets probably leak a lot of sound / have resonances... a few mm of PLA or ABS is nowhere near 15mm MDF in overall stiffness or mass. I would modify this design and 1) make it less ugly, 2) add a hollow cavity to add plaster, resin, or concrete.

Also, big missed opportunity in terms of making the inner walls regular. You can make them any shape you want to break up resonances / standing waves. Why flat?