I hope you don't mind my dredging this up a year later... nice job on the speakers, and really helpful that you shared your work and process! Thank you.
I like the waterjet-cut template idea. Mind if I ask which plastic you used, and the approximate cost? Did you also consider having the baffles CNCed?
My ceramic BMR kit has been collecting dust due to "life", but I'm planning on changing that. My current concept is to make the housing out of concrete because I've always thought it would be interesting to mess around with that material, to pair with a wooden baffle.
FYI
VIRTUOSO By Gravelli
China-
Concrete Speaker
https://www-hifidiy-net.translate.g...http&_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US
Granite Speaker Cabinet
https://www-hifidiy-net.translate.g...http&_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US
China - HIFIDIY.NET
https://www-hifidiy-net.translate.g...uto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_sch=http
Google Translate -Chinese to English
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Thanks for those examples!
For some of the concrete ones I keep wondering... if you finally have a fluid material to work with, why would you then make a plain box?? I'm planning on making the cross-section an oval for this one to keep it simple, with a flat baffle to not mess with the crossover.
I don't want to hijack @NORTH4's thread, so when I do build them I'll start a new one and link it back here.
For some of the concrete ones I keep wondering... if you finally have a fluid material to work with, why would you then make a plain box?? I'm planning on making the cross-section an oval for this one to keep it simple, with a flat baffle to not mess with the crossover.
I don't want to hijack @NORTH4's thread, so when I do build them I'll start a new one and link it back here.
Hello, I dont mind 🙂 and thank you, i am still enjoying them.
The plastic used for the templates is HDPE, a high density plastic. cost was about 380$. I considered having the templates CNCed but i didnt find any local businesses and was not aware online services existed. If i did it again i would have gone through SendCutSend.com for a cheap template then transferred it to whatever material i wanted.
I have a sheet of 3/4" baltic birch collecting dust from a recent project. I can make a couple finished baffles if you cover shipping?
Another way -
Wolf's Stance Speaker
https://techtalk.parts-express.com/forum/tech-talk-forum/1293229-the-stance-speaker-build-thread
Wow, what a kind and generous offer! Let me see how my design develops--a duplicate of your templates could be very helpful.
I also really appreciate the additional link to SendCutSend.com--I'm curious to explore their offerings!
Here's what I'm expecting my BMRs to look like. I preferred the look of towers to monitors on stands for this project, so I explored using the volume of the "integrated stands" to make the towers slimmer and not package as much air. However, when I posted on the AVS forum I was cautioned that the elongated aspect ratio would change the box tuning.
To my amazement, Dennis contacted Paul Kittinger, who generated ML TL parameters that are optimized for this very different enclosure shape! Incredible that they would take the time to support my one-off variant of the highly refined BMR.
I decided to have some fun exploring high performance concrete, so am intending to create everything but the baffle in a molded form, after which they'll be bonded to the baffle, faired and painted. They're intended to be 40.25" high, 10" deep to the back of the oval, and use the standard 8" baffle width. I haven't decided on the foot/plinth treatment yet... working out how to have them on small casters for easier movement. Using a 3/4" wall in GFRC puts the concrete shell currently at about 55 lbs, so probably 75-80 for the whole speaker.
Sure thing, happy to help! If a duplicate of the template is more useful i can do that. Send me a PM when your ready and we can work it out.
I really like where your going with the build, i will be following. Im interested to learn along the way how you make the concrete forms (many pictures please haha). Concrete isnt something ive had the chance to work with yet, Im always in envy seeing builds with this material and the bmr's are going to look amazing as a floor stander. I nearly made mine with built in stands to hold the crossover, i wish i had.
Thats awesome Dennis and Paul were able to help you out with design. I also had a positive experience with Dennis during my build.
Thanks again, and I very might well take you up on the template offer!
I'll create a dedicated BMR slim tower build thread when I get around to making the molds/forms and rest of the speakers. I'm not experienced with concrete so we'll see how things go!
You could still convert your BMRs to towers--add stands in the same wood or bond/fair with a different finish, build them as new towers and migrate parts, or go wild with a new design that leverages non-traditional speaker materials. 🙂
I'll create a dedicated BMR slim tower build thread when I get around to making the molds/forms and rest of the speakers. I'm not experienced with concrete so we'll see how things go!
You could still convert your BMRs to towers--add stands in the same wood or bond/fair with a different finish, build them as new towers and migrate parts, or go wild with a new design that leverages non-traditional speaker materials. 🙂
more concrete (Alumina cement?) speakers (spheres)-
Sophera Loudspeakers-Australia
http://www.sophera.com.au/index.php/design/why-concrete.html
Sophera Loudspeakers-Australia
http://www.sophera.com.au/index.php/design/why-concrete.html
Those are nice but look like meteorites in a museum. The problem of having them properly fit in space doesn't challenge them, err...
Doing a test cut first! Always an excellent idea. 🙂 The 5/16" template bushing means that the routing template is 1/32" oversized, as it were?
The project so far is going... like a project. So, I'll need to route a bunch of identical forms for the concrete mold... say, I never did mount that router plate in the wing of my table saw... wait where the heck Is the plate (add 30 minutes of searching)... need some scrap wood the same thickness... this one's perfect but too short... that one's long enough but slightly uneven... run it through the jointer... small knot flies out of the guide surface... etc.
Why does Indonesia or Denmark or Canada or USA have speakers clad in timber?
The have plenty of tall trees!
Concrete?
We got sand y’all
We'll just call these the "Aussie Edition"... fair enough, I was born there! Though in terms of living environment I'm a USA East Coast/West Coast/Swiss hybrid. 🙂
Plus, there are aspects of the SF Bay Area that feel remarkably similar. Minus a few marsupials.
Going back to "it's a project" theme, my 3D printer was running full speed on the back template when I realized I'd made the wrong thickness offset. After correcting it, it's running at about 5% of its normal speed... which it's never done before. Absolutely bizarre.
Plus, there are aspects of the SF Bay Area that feel remarkably similar. Minus a few marsupials.
Going back to "it's a project" theme, my 3D printer was running full speed on the back template when I realized I'd made the wrong thickness offset. After correcting it, it's running at about 5% of its normal speed... which it's never done before. Absolutely bizarre.