Aagas, easy composites sell loose CF strands, graphite powder and CF milled powder, which can be added to expoy, see below:
https://www.easycomposites.co.uk/filler-powders-and-additives
here are two examples. Recorded using an iphone. The speakers in the video are my latest project. They are actually a hybrid of DML and piston.
However they sound the same (above 250 Hz) as the speakers I showed in the previous post. The panel is built in the same way.
@Sandasnickaren
Lovely!
Would you like to talk about your latest project? That is, what's behind the panel, and so on...
Lovely!
Would you like to talk about your latest project? That is, what's behind the panel, and so on...
Sandasnickaren.
Ha ha I love it, nothing like a bit of heavy metal to get things moving ✌️
Have you listened to my du hast recordings.
Your panels in the wall ideas has reminded me of an idea I was thinking of trying.
G A Briggs describes using a cone speaker in a box but mounting it so the driver has a gap between the driver and panel.
The gap acts as a port to drive the bass and mimics a free edged cone but without the low frequency resonance of the free edged cone.
This gives a sort of open baffle sound .
I did this with a 8" cone many years ago and it sounded very nice.
I wonder if mounting a driver or panel in such a way in a wall would also work ?
Steve.
Ha ha I love it, nothing like a bit of heavy metal to get things moving ✌️
Have you listened to my du hast recordings.
Your panels in the wall ideas has reminded me of an idea I was thinking of trying.
G A Briggs describes using a cone speaker in a box but mounting it so the driver has a gap between the driver and panel.
The gap acts as a port to drive the bass and mimics a free edged cone but without the low frequency resonance of the free edged cone.
This gives a sort of open baffle sound .
I did this with a 8" cone many years ago and it sounded very nice.
I wonder if mounting a driver or panel in such a way in a wall would also work ?
Steve.
The question is "end grain balsa" in 1.5 or 2mm. Have you found some? Boards 10cm by 1m in different thickness are quite aesy to find.
I can easily get 1.5-2mm balsa sheets, but I’m struggling to find end grain sheets at this thickness. See attached pic.
Thanks
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Sandasnickaren’s speakers sounded great, so maybe not worth the hassle trying to source end grain and just use standard sheets glued together, as Sandasnickaren has done. 👍
No direct link with DML but might be interesting for all DYIer : screw head repair around 10s and later the molding technique. I found also the smoke suspect!
@Sandasnickaren and others...
If you want the image you insert sized to the amount you like, just click on the inserted image, and pull from the bottom right corner. When you click on the inserted image there'd be 4 bold squares at each end. The image can be pulled to size from any of them.
If you want the image you insert sized to the amount you like, just click on the inserted image, and pull from the bottom right corner. When you click on the inserted image there'd be 4 bold squares at each end. The image can be pulled to size from any of them.
Also worth considering is the density of balsa that can vary between 60 to 250 kg per kubik meter. I have used the ligthest I could find which was roughly 100kg/m3.
I’ve considered making an endgrain core (I do have the equipment to do it). It would be intresting to see/hear if it makes a difference. Maybe later on.
What was the weight of the panel without the carbon film cover? Or, with the carbon film cover?
As requested,
These are designed to be in a closed box or in-wall. I call them hybrid as they operate both as DML and piston. The size is roughly the same as an 15 inch driver ie SD 912 cm2,but the moving mass is only 60g and the BL 29 Tm. Xmax 10mm p-p.
There is a ”regular ” foam surround I made from 1 mm EVA foam. It’s U shaped.
I’m using 6 exciters to drive the panel.
’Frequency range when mounted in-wall is 30-20000 Hz. It’s most likely possible to push them down to 20 with a bit of eq.
measurements from 1m and nearfield few cm.
Attachments
Can you give the dimensions of the box, length and breadth of the panel? How are the drivers connected?
I just checked, 10g is 2 A4 printer paper. 26g is just 5 A4 paper. Is your 2nd project panel that light too?
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So, the lightness of the panel is the most important factor, other than how it is made - a composite. Both Gobel and Herger were talking about very light composite panels. Actually they are featherlight. @Sandasnickaren's panel is lighter than Gobel's. Thanks pal, I'm going to read both Gobel's and Herger's patents very carefully. You've done a superb job of proving it! 🙂