[Hobbsmeerkat]

Bambu P1P just arrived printed a "Benchie" within 20 min.

I sliced the waveguide in the Bambu slicer with the same settings and each waveguide will take an estimated ~4.5 hours

For reference, my Ender 3 takes 19.5hrs for the same print. That's a roughly 75% reduction in print time.

[mkrawcz]

Bambu P1P just arrived printed a "Benchie" within 20 min.

I sliced the waveguide in the Bambu slicer with the same settings and each waveguide will take an estimated ~4.5 hours

For reference, my Ender 3 takes 19.5hrs for the same print. That's a roughly 75% reduction in print time.

Bambu is the best. 

[mlundy57]

Bambu P1P just arrived printed a "Benchie" within 20 min.

I sliced the waveguide in the Bambu slicer with the same settings and each waveguide will take an estimated ~4.5 hours

For reference, my Ender 3 takes 19.5hrs for the same print. That's a roughly 75% reduction in print time.

Better tool = better results for sure

[BrandonB]

Better tool = better results for sure

Do you have any ideas with this new speaker design?

[Hobbsmeerkat]

Better tool = better results for sure

I need to tweak the speeds just a bit, as there are some areas where it printed just a little too fast and you can see some under-extrusion.
But overall, for a 4.5 hour test, the quality is solid, gunna slow down the wall speeds just a smidge until it looks just as clean as the Creality printer.

[william2001]

Can melamine foam be used in the tweeter cup?

[Hobbsmeerkat]

That will likely too stiff/dense to be practical
loose fiberglass, extra soft felt, or possibly a couple large cotton balls are likely your best options depending on what you have access too, the trick is to loosely fill it.
Too much stuffing and you'll lose the bottom end, too little and you'll get reflections/standing waves within the back cup which will really mess up the tweeter response.

We're still working on figuring out the best option to gauge what is the correct amount of stuffing, but we really need a test bench that will allow us to push a back cup up against the tweeter. Rather than putting in a random amount, gluing it, let it cure, then test, cut off the cup and try again.

[william2001]

Thanks.  It would be helpful to nail that down for good unit to unit consistency and expected results there.  I was just asking because I have located a good source for genuine Basotect foam.  Would be easy to trim to size for form, fit, and function.  With the low crossover point of this tweeter in mind, the sound absorption coefficient of Basotect looks to be quite effective...., ~0.9 @1kHz with a 2" thickness (I don't know how deep your tweeter cup is).  Pick up some Mr. Clean Magic Eraser pads if you get a chance for your beta test.  Some guys like a combination of foam and stuffing working together.  Maybe that could also be tested... just some thoughts..             

[BGFan2024]

Hobbs how do these sound compared to the NX-Studio's and how are they different.  Do they serve different purposes better?

This is my question as well, sort of. I think getting NX-Studios and subs will be highly unlikely for me ($, SAF, etc), but this might be a good compromise.

(1) Also, how much improvement would these be over my current X-LS Encores? Similar low end? (I know Danny said in a video that from X-LS Encores to NX-Studios would be like going from 5-9 on a scale of 1-10.

(2) Will the tower version extend the low end beyond the bookshelf model? Beyond X-LS Encore low end or about the same?

[Hobbsmeerkat]

1) The bottom end will be very similar, with the X-LS Encore having just a little more impact, due to the larger woofer, but the NX-Bravo will have a larger overall presentation thanks to the lower crossover point, and better clarity throughout the upper midrange and treble. Where it falls short of the Studio IMO is in some of the depth/layering of the soundstage, and also lacks the "airy" or "spacious" top end that the open backed tweeter provides.

2)The updated MTM tower version will put the bottom end closer to the range of the X-SLS tower (~45Hz), but with higher overall efficiency (~90dB vs 87dB) and better midrange performance since the work is shared between 2 woofers.

[BGFan2024]

Thanks, Hobbs! Sort of what I figured about comparison of the NX-Bravo and Encore X-LS.

[Hobbsmeerkat]

just a quick heads up that we have flatpacks/cabinets available to order via the site.
We're just about sorted with everything we're waiting on more filament to make some gaskets for the waveguides.

Once that's done, I'll be able to contact everyone on the waiting list that things are ready to ship.

[Presb4]

This will probably be my next speaker build. Great work guys.

[mkrawcz]

Got mine up and running. These are much closer to the NX-Studios than they are the XLS Encores IMO. They sound fantastic and I just fired them up.

[Hobbsmeerkat]

The main thing the NX-Bravos lack from the Studios imo is the open/airy soundstage of the open-backed tweeter, but overall are very similar.

The nice thing is that the ports we supply are a fair bit longer than they need to be, which is great for near-wall/desktop placement, allowing for additional bass extension closer to 45Hz without any "boom"

Not ideal for pulling the speakers out into the room though, where the ports need to be cut short (down to ~3.5") for a proper 55Hz roll off point

[william2001]

I appreciate the extra thought concerning bass response and the port length based on where the speaker is to be placed.  It's another thing that's nice about DIY vs store bought, the ability to customize and "dial in" a project to better fit a particular situation.  My pair will live close to a wall. 

I'm currently awaiting my flat packs.  Tweeter assemblies are finished and ready.  Well on my way with the crossovers, getting close to finalizing those..

[jabouley]

Thanks Hobbs for printing all of these waveguides. Is there any issue with sanding these to take some of the ridges out and painting them so that they look a little smoother?

[dayneger]

You've got me very curious about the relative performance of this new waveguide. 

How does the 3D printed geometry measure compared to the waveguides cut into the baffles, e.g. the Studio?  It looks visually more "sophisticated" in the surface lofting.

I'm particularly interested in anything that helps the system sound good from many listening angles.

Cheers, and congrats on the new addition to the NX line!

D.

P.S.  Being able to cross as low as 1 khz is pretty remarkable!

[Hobbsmeerkat]

Thanks Hobbs for printing all of these waveguides. Is there any issue with sanding these to take some of the ridges out and painting them so that they look a little smoother?

No problem with that at all, just make sure the primer/paint is suitable for plastics like PLA.

You've got me very curious about the relative performance of this new waveguide. 

How does the 3D printed geometry measure compared to the waveguides cut into the baffles, e.g. the Studio?  It looks visually more "sophisticated" in the surface lofting.

I'm particularly interested in anything that helps the system sound good from many listening angles.

Cheers, and congrats on the new addition to the NX line!

D.

P.S.  Being able to cross as low as 1 khz is pretty remarkable!

The waveguide was based on a series of iterations I did, with the main goal of trying to keep them within the parameters of the old BG faceplates.
Danny's NX-Treme waveguide has a custom left/right sides that are similar to what I ended up designing in the end, as it allows for a smoother horizontal off-axis response than the standard NX waveguide, which has a bit more of a stair-stepped response.

they're a bit hard to compare directly tho, as the standard NX waveguide is also about 1.35" deep, and the NX-Bravo is only 0.8725" deep, though I could technically make it as deep as 1" with minimal adjustments which will boost the bottom end even more, but I haven't printed one out to compare it just yet.
the Standard NX was also designed around OB use so its design needs to be different than the new one which is centered around the more sealed-backed design.

Another thing to consider is wall thickness. The first tests of the NX-Bravo were done with a waveguide using 4-layer thick walls.
Bumping that up to 8 layers increased the bottom end output a bit, allowing for me to make use of the additional extension.
A 2-wall version would likely suffer down low a bit as some of that lower frequencies will end up passing through the thinner walls and interacting with the 40% infill.
A fully solid version would likely boost the bottom end a little further but it would take forever to print and use up a fair bit more filament.

you can see similar results in the different measurements Danny showed in the initial video between the thin-walled 3" deep plastic horn and the 3" deep MDF horn, with the MDF was smoother overall with better bottom end extension. had the plastic version used thicker walls it would have been more similar to the MDF version.

PLA

vs MDF

[dayneger]

No problem with that at all, just make sure the primer/paint is suitable for plastics like PLA.

PLA can be a real pain to get smooth, especially with sanding.  Probably better to spray with a paint in light layers and sand that.  I've never tried one of the chemical processes, though.

Did you cost out a batch run on a carbon printer?  Now that you have your geometry dialed, that might be an option.  Or make a golden, smooth sample and cast them in polyurethane from silicone molds.  Lots of ways you could make them over time.

The waveguide was based on a series of iterations I did, with the main goal of trying to keep them within the parameters of the old BG faceplates.
Danny's NX-Treme waveguide has a custom left/right sides that are similar to what I ended up designing in the end, as it allows for a smoother horizontal off-axis response than the standard NX waveguide, which has a bit more of a stair-stepped response.

they're a bit hard to compare directly tho, as the standard NX waveguide is also about 1.35" deep, and the NX-Bravo is only 0.8725" deep, though I could technically make it as deep as 1" with minimal adjustments which will boost the bottom end even more, but I haven't printed one out to compare it just yet.
the Standard NX was also designed around OB use so its design needs to be different than the new one which is centered around the more sealed-backed design.

Oh, you were targeting the old BG faceplates.  Makes sense.  I didn't realize that the NX-Treme has asymmetrical waveguides, thanks for mentioning it (although did Dannie say they're the same in the video?).

Those much larger, puffy waveguides looked really interesting.  Did they get discarded as a concept too quickly?

Another thing to consider is wall thickness. The first tests of the NX-Bravo were done with a waveguide using 4-layer thick walls.
Bumping that up to 8 layers increased the bottom end output a bit, allowing for me to make use of the additional extension.
A 2-wall version would likely suffer down low a bit as some of that lower frequencies will end up passing through the thinner walls and interacting with the 40% infill.
A fully solid version would likely boost the bottom end a little further but it would take forever to print and use up a fair bit more filament.

It sounds as though it'd be worthwhile to explore a few of the other production methodologies, which might also enable you to optimize the waveguide for stiffness or damping.  Reaction injection molding (RIM) is one that comes to mind... tooling is often quite a bit less since it's a low-pressure process, and you can have significant variation in your wall thicknesses (which is a challenge with standard plastic injection molding), at the expense of higher piece part cost.  Or again, the urethane casting mentioned above.  My guess is that if the orders ramp, you'll quickly find you have better things to do with your time than tend a 3D printer in production and answer customer requests about when their NX-Bravos will finally ship!   

As an aside, your NX header on the website might need to change with the exciting NX-Bravo addition--currently it's "Reference Open Baffle".