Small 2-way speakers with linear on-axis and power response characteristics (Scan Speak and SB Acoustics drivers). H&V off-axis measurements included

[Nullgator]

I don't currently have the option of milling the holes and recesses into the front of the chassis.

I was thinking of making the case out of plywood and only 3D printing the front. (18 mm thick - maybe thicker with either 60% infill or 10% + filled with sand)

This way, I can use my printer to design the front in multiple colours (similar to the Sonus Faber speakers). And may try out suggested angled edges..


Would you say that would work without any drawbacks? Which would be better, 60% infill or sand filling?
... Or would one 3D printed part already have all the disadvantages of 3D printing enclosure?

Might be worth trying both as long as you don't mind the the time and filament use, afaik there is not direct testing between these two baffle constructions.


I've also seen decidamp and Weicon Flex 310M Classic used as effective CLD materials. Decidamp seems to only come in large quantities and the adhesive would need to be injected into the part somehow. In both cases CLD works best when the damping layers are ~1mm so to get the greatest effect you'd have to play around with your infill settings or add internal walls of some sort. Or you could just laminate layers of some material together, which would also make the recesses relatively easy.

 

[klapper]

Sand on its own, or combined with resin? Plaster of paris mixed with PVA is another fill option I've seen used, as well as some concrete mixes. I haven't seen direct comparison of them all though - just different infill ratios compared, and comparing plaster of paris with and without the PVA. The mineral filled resin and concrete infills come from using 3D printed parts (among others) to make CNC tool frames where vibration resistance is also needed. They found using a sander as a vibration source during filling speeded up flow and reduced voids and settling time. Is the 3D printer you have access to big enough to print the baffle in one piece? Joining parts accurately is one of the disadvantages that may or may not apply.

Yes i use the Bambu H2D. I will print the buffle in one part. The video mentioned above uses more walls for better stiffness, 30% infill (gyroid) - PETG was a little better butt it has lower stiffness and can be scratched easier.
I could fill it with VERY fine sand (just sand, nothing else). But i think that gyroid with air will be better.

I checked a local dealer that want's 25€ per hole... That's too much.

 

[klapper]

Might be worth trying both as long as you don't mind the the time and filament use, afaik there is not direct testing between these two baffle constructions.


I've also seen decidamp and Weicon Flex 310M Classic used as effective CLD materials. Decidamp seems to only come in large quantities and the adhesive would need to be injected into the part somehow. In both cases CLD works best when the damping layers are ~1mm so to get the greatest effect you'd have to play around with your infill settings or add internal walls of some sort. Or you could just laminate layers of some material together, which would also make the recesses relatively easy.

Yes. I will likely try different approaches and check if i can hear a difference. Filament is not a problem. But i will stick to classics (PLA, PETG, ABS...)

 

[somebodyelse]

I could fill it with VERY fine sand (just sand, nothing else). But i think that gyroid with air will be better.

Sand would provide damping and add mass, so lower resonant frequency and broader, lower resonant peak. At least in theory. Whether that's an advantage or not may depend on whether it gets pushed towards or away from other resonances. You could model this, but then you'd probably have to validate your model by making and testing both anyway - so you may as well make it then test without and with sand fill - if it's worse you can empty it again.

 

[klapper]

Actually I got a better Idea. I will buy 9mm plywood just for the front, 3D print stencils with many little holes in a circle and drill them into the 9mm wood. Cut out the remainings with a jigsaw and sand it. On the 9mm wood i will glue a 3D printed 9mm face with all recesses, some multi color silver accents and a "Mechano" lettering. Since I didn't think of it immediately, I thought I'd post it if someone else has this problem. I would say this is a valid way of combining a 3D print with wood enclosures without overthinking it.

 

[codercodi]

For dampening material, I know polyfill is an option. However, I also really liked the clean approach some folks took of lining the walls with felt pads and members such as Woddy99 suggest wool felt as described in a post here.

Would something like this work?

https://www.amazon.com/TroyStudio-Acoustic-Panel-Soundproofing-Absorbing/dp/B07T1DJF6P

Or should I spring for wool felt such as this

https://www.amazon.com/Pressing-Zealand-Ironing-Quilting-Supplies/dp/B0D3TGL19Y

 

[carbidetooth]

For dampening material, I know polyfill is an option. However, I also really liked the clean approach some folks took of lining the walls with felt pads and members such as Woddy99 suggest wool felt as described in a post here.

Would something like this work?

https://www.amazon.com/TroyStudio-Acoustic-Panel-Soundproofing-Absorbing/dp/B07T1DJF6P

Or should I spring for wool felt such as this

https://www.amazon.com/Pressing-Zealand-Ironing-Quilting-Supplies/dp/B0D3TGL19Y

I would say neither would offer any advantage over polyfill. When it comes to cabinets, there are two things that would concern me. Damping the panels themselves changes the resonant frequency of the box material. Fill changes the way backwave from driver moves through the cabinet. Latter link may offer a bit of both if adhered to interior, but you're not trying to "soundproof" the cabinet which is stated use for first link. Density of fill material can have the effect of reducing cabinet volume. What is your goal in finding an alternative to polyfill?

 

[codercodi]

I would say neither would offer any advantage over polyfill. When it comes to cabinets, there are two things that would concern me. Damping the panels themselves changes the resonant frequency of the box material. Fill changes the way backwave from driver moves through the cabinet. Latter link may offer a bit of both if adhered to interior, but you're not trying to "soundproof" the cabinet which is stated use for first link. Density of fill material can have the effect of reducing cabinet volume. What is your goal in finding an alternative to polyfill?

No specific goal other than for it all to be neat. But if 80g polyfill is good enough acoustically than I’ll just do that

 

[klapper]

Finished my speakers today. The 1cm 3D printed front is sealed onto the 9mm wood front. The wholes are for extra screws (mainly for the optics) that i still need to buy. (The silver details look white on photos)
The sound is awesome. Didn't expect so much. But I'm surprised. I rounded the edges. Unfortunately I have no comparison, but would say it benefits the dispersion. (If my math was right > 3kHz) The speaker realy disappeared when i close my eyes i could never guess where they are located exactly.

 

[codercodi]

These Dayton Audio 27uF caps are MASSIVE. I didn’t think about this. LOL

 

[klapper]

These Dayton Audio 27uF caps are MASSIVE. I didn’t think about this. LOL
View attachment 497584

Most of my parts we're surprisingly huge. I had to rearrange the parts a little but too. But make sure to keep the Inductor in the correct position/ alignment as in the original design. Else they will effect each other.

 

[wineds]

These Dayton Audio 27uF caps are MASSIVE. I didn’t think about this. LOL
View attachment 497584

The PCB was designed to fit parts linked in the first post of the review thread. viz (from github readme) :

BOM is as per component links in the first post of the ASR review here : https://www.audiosciencereview.com/...chano23-open-source-diy-speaker-review.54066/

Alternatively see simple BOM here : mechano23_xover_schematic.xls

 

[codercodi]

The PCB was designed to fit parts linked in the first post of the review thread. viz (from github readme) :

BOM is as per component links in the first post of the ASR review here : https://www.audiosciencereview.com/...chano23-open-source-diy-speaker-review.54066/

Alternatively see simple BOM here : mechano23_xover_schematic.xls

No problem. I am in the US so had to order based on availability from PE. So far seems like the 27uF is the biggest issue. The coils are a little off too but I think I can make it work. What are you thoughts on things touching like this? I think I could make it work if I squeeze them in like this.

Edit: I also wanted to add - such excellent work all around on the PCB. Thank you!

 

[wineds]

It should still work OK. But you may need to use liberal amounts of neutral cure silcone and/or "liquid Nails" to ensure nothing buzzes or rattles. Note that the completed crossover also needs to fit though the woofer hole.

 

[codercodi]

Yeah. My panels are not yet cut. So will have to think about this a bit. Probably should just order new 27uF caps. I can't seem to be able to find any Jentzen non-polar ones in the US.

 

[wineds]

This one is listed as 7 x 18mm but I'm skeptical if that is true :

Jantzen Audio 27uF 400V Cross Cap Crossover Capacitor

Jantzen Audio 27uF 400V Cross Cap Crossover CapacitorProduct FeaturesDimensions: (Ø 7mm - L: 18mm)The Cross Cap is offering a high-level of performance and quality at a very reasonable price point. A great multipurpose entry-level audiophile capacitor. A single foil (standard type MKP/PP foil)...

www.parts-express.com

and its more expensive @~ $16 each.

 

[codercodi]

This one is listed as 7 x 18mm but I'm skeptical if that is true :

Jantzen Audio 27uF 400V Cross Cap Crossover Capacitor

Jantzen Audio 27uF 400V Cross Cap Crossover CapacitorProduct FeaturesDimensions: (Ø 7mm - L: 18mm)The Cross Cap is offering a high-level of performance and quality at a very reasonable price point. A great multipurpose entry-level audiophile capacitor. A single foil (standard type MKP/PP foil)...

www.parts-express.com

and its more expensive @~ $16 each.

Well a pickle. Ill try to make it work and fasten everything down

 

[Bwaslo]

Gotta love when AI provides a 'schematic'. Like, wtf is this??

 

[Ktacos]

Please stop using AI for speaker design... It has no idea what it's doing and only gives you bad results.

Yeah, that schematic is just utter nonsense.

 

[Newman]

I'm not sure if this is the right place for this, but I'll give it a try. I asked Gemini AI...

Please check the official forum policy on use of AI. Although it doesn't explicitly ban your post in this location, Amir felt compelled to create a policy because quite a lot of members here don't welcome them. All they do is distract conversations between humans on a favourite topic into a discussion of how smart (or not) is AI, let's discuss AI. No thanks. Amir recommends (policy note #5) that members only post AI content on a topic if the member knows as much as AI on the topic...which I take to mean the member will be automatically evaluating the AI response with some expertise. Which has not happened here.

There is a master thread for AI discussion. Maybe post there. Although the one you contributed is, as already pointed out, utter garbage. I won't be discussing it.