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Revel M105 Copy DIY build

617

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I 3D printed lots of parts when I built my LXMini's. Here is a test fit.

View attachment 182552

Using a sparse build, but with extra outer layers meant I could fill the voids. For the outer surfaces I used XTC-3D from Smooth-On (https://www.smooth-on.com/products/xtc-3d/), which brushes on and sands easily. I finished everything with a coating of truck bed liner, and then a rattle can of white on top of that.


View attachment 182553

The B&W's are now just used in a spare bedroom. Should really sell them.
Any other build photos? What did you fill the voids with?
 

D!sco

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I've thought about this as well. I have a 3dp with a 300mm square bed, so I have space to make a baffle for a mid/tweeter.

One thing you could do is use a very sparse honeycomb infil with no shell on the back side of the baffle, so that you end up with a bunch of hexagonal cavities you can then fill with some kind of heavier inert material. You essentially make a shell which is then filled with bondo or epoxy mixed with sawdust or rubber particles.

The problem really becomes the fact that 3d printed surfaces tend not to be that smooth or attractive but there are ways you can deal with that.
I spend so much time painting my speakers I can't imagine not spending three days sanding a layer of bondo off the top to mask the print lines. Not having to buy a bunch tools to make cuts/mistakes? Priceless. Love the idea of padding printed infill. That's worth experimenting with outside of speakers.
 

Madjalapeno

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I spend so much time painting my speakers I can't imagine not spending three days sanding a layer of bondo off the top to mask the print lines. Not having to buy a bunch tools to make cuts/mistakes? Priceless. Love the idea of padding printed infill. That's worth experimenting with outside of speakers.
I agree it's promising but I hate sanding bondo. Too many hours of my life.

Do you know of a good primer for PLA?
 

howard416

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I agree it's promising but I hate sanding bondo. Too many hours of my life.

Do you know of a good primer for PLA?
If you go with a premium lightweight body filler (i.e. not Bondo) it won't be so bad. Try Evercoat Rage Ultra or Z-Grip.

I mean, sanding generally sucks but "kinda sucks" is still way better than "sucks ass". OK, now the word sounds funny.
 

D!sco

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I agree it's promising but I hate sanding bondo. Too many hours of my life.

Do you know of a good primer for PLA?
I honestly haven't even tried it yet.
 

617

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If you go with a premium lightweight body filler (i.e. not Bondo) it won't be so bad. Try Evercoat Rage Ultra or Z-Grip.

I mean, sanding generally sucks but "kinda sucks" is still way better than "sucks ass". OK, now the word sounds funny.
I've used some of the evercoat products, I had one which is more like a cream. I'd avoid bondo in the future, doesn't spread very well.
 

howard416

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I've used some of the evercoat products, I had one which is more like a cream. I'd avoid bondo in the future, doesn't spread very well.
What I learned from my pizza oven (long story) is that the substrate has to be non-porous and not have a tendency to suck moisture/liquid in. I tried to put body filler on raw plywood and it quickly became a disaster. I should've applied a couple of layers of B-I-N or whatever to act as a barrier, first.

Not saying that's why you had issues, but just putting it out there in case anyone else is thinking about doing something similar.
 

D!sco

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I will say every time I've considered 3D printing for an audio product, I think clear PETG. An alcohol soak and some futzing in the oven is supposed to produce some incredible results. Hell, I'd do it with a waveguide, like the SEAS Loki. I just can't be lazy and have dangling wires or hot glue beads everywhere inside if I do. Or pieces of tape with +/-, W/M/T, "Front" strewn about. Ugh.
 

TimVG

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Really nice project, and result! Congrats.
 

Lopsided

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The phase shield isn't going to boost the on axis. It looks to me that you have not compensated the mass and inductive rolloff that occurs in constant directivity waveguides. A 6dB filter between 10 and 20K (driver dependent) is usually added to compensate, there would be less need for a padding resistor as it cuts the gain from the waveguide loading.
I’m confused by the mass rolloff part. Isn’t driver bandwidth supposedly independent of mass?

Debunking the Myth that a Lighter Diaphragm Enables a "Faster" Speaker Driver
 

beagleman

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As great as this looks, physically and in measurements, this just begs for a dual woofer version, with 2-8 ohm woofers paralled!

That would allow some awesome output and decent sensitivity.
 

Lopsided

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No, where did you get that? There's a natural low-pass from the moving mass of the driver, which drops in frequency as you increase the mass.
The post I linked seem to contradict this, so I’m confused. I get that impedance rises when frequency rises, but don’t understand the mass part.
 

fluid

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The post I linked seem to contradict this, so I’m confused. I get that impedance rises when frequency rises, but don’t understand the mass part.
It is not contradictory. That link is about acceleration and force. Transient "speed" requires greater bandwidth, if you take away the high frequencies there is no way for anything to rise quickly. Lowering the mass increases the bandwidth at the top end.

https://jblpro.com/en/site_elements/tech-note-characteristics-of-high-frequency-compression-drivers

https://audioroundtable.com/misc/Maximum_Efficiency_of_Compression_Drivers.pdf
 
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McFly

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Agreed, if one were to make a tower you could simply add another woofer as a .5 way to boost sensitivity, and reduce IMD on the upper woofer due to less boost required on the low end. Would be a nice little tower speaker for sure.

So update: I’m Still waiting for my calibrated mics to show up, unfortunately shipping by usps to nz has been halted. I need these calibrated mics to turn up so I can nail the crossover down, then tidy up the boards and finish the cabinets. The speakers will then likely be gifted as wedding presents. Just living with these speakers for the last weeks they do sound amazing but I feel they could be tilting up slightly more than my measurements would suggest. So still a bit of work to do before I donate to the forum and edit the first post with a final crossover design. I have managed to get a bend on the ports and lower the tuning, which really did help level out the bottom end and take away a bit of boom.

For my next project I’ve just had some 8” waveguides printed, and eagerly await the release of the 8” purifi woofer. Hoping to upsize this design done here to 8 inch.
 

Tangband

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Agreed, if one were to make a tower you could simply add another woofer as a .5 way to boost sensitivity, and reduce IMD on the upper woofer due to less boost required on the low end. Would be a nice little tower speaker for sure.

So update: I’m Still waiting for my calibrated mics to show up, unfortunately shipping by usps to nz has been halted. I need these calibrated mics to turn up so I can nail the crossover down, then tidy up the boards and finish the cabinets. The speakers will then likely be gifted as wedding presents. Just living with these speakers for the last weeks they do sound amazing but I feel they could be tilting up slightly more than my measurements would suggest. So still a bit of work to do before I donate to the forum and edit the first post with a final crossover design. I have managed to get a bend on the ports and lower the tuning, which really did help level out the bottom end and take away a bit of boom.

For my next project I’ve just had some 8” waveguides printed, and eagerly await the release of the 8” purifi woofer. Hoping to upsize this design done here to 8 inch.
Fantastic work !:).
One hint/tip from me : Its always good to have or borrow a really good sounding reference loudspeaker to compare with in your listening room. There are so many parametres that can be changed in a loudspeaker regarding the crossover.
I borrowed two Genelec 8330 for two days of measuring and listening/comparing when I did the final construction of my active loudspeaker HYBRID .
 

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McFly

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Fantastic work !:).
One hint/tip from me : Its always good to have or borrow a really good sounding reference loudspeaker to compare with in your listening room. There are so many parametres that can be changed in a loudspeaker regarding the crossover.
I borrowed two Genelec 8330 for two days of measuring and listening/comparing when I did the final construction of my active loudspeaker HYBRID .
Nice!! I dont have access to any genelecs - but I do have DBR62's which are a pretty safe sanity check.
 
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