What is the best way to construct an curved loudspeaker cabinet for daily pro use?
An examples is the curved cabinet from danley, type sm lpm.
gr. marcel
An examples is the curved cabinet from danley, type sm lpm.
gr. marcel
Construction curved loudspeakers
- Thread starter Marcel de Graaf
- Start date
My experience with this is thirty years out of date but... Bending plywood involves heat and force. Reasonably practical with thin plywood, impractical with the plywood thicknesses normally encountered in live audio speakers.
One of the standard methods is kerf bending
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Kerf Spacing - Kerf Bending - Woodworking Archive
The spacing between kerfs or the width of the ribs not only will affect the maximum radius that you can bend, but also how smooth the bent piece will look. The
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Good - that's well within the realm of basic DIY! The curved horn would have been a different matter...
The simplest way is probably to draw and then hand-shape the curve desired in, say, 12 or 18mm ply, then make a few copies of it by using the technique of copy routing.
Now fix these formers in a row (as wide as the panel you wish to reproduce) to a stiff and strong baseboard - this is the reusable jig over which you will form the finished panels. Material-wise you have the choice of laminating hardboard (Masonite in the US?), thin plywood, thicker flexible plywood and flexible MDF, the last of which has to laminated onto at least one base layer, which can be thin ply or whatever, to maintain its shape. Lamination glues and clamping techniques are well-covered on YouTube. Laminated ply would be most suitable for PA use due to its greater strength and lower density.
If you wanted to go really lightweight and high tech, these same ideas can be used to laminate aluminium over a honeycomb core, or fibreglass sheet over PU foam for example!
There are plenty of great YouTube videos showing all the steps of curved panel construction, primarily for furniture, but the techniques are identical.
As Rob suggests, kerf cutting is another method of making curves in wood, however it can be more time-consuming and might not result in a perfectly smooth external curve. Both methods have their pros and cons.
Good luck, Carl
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Marcel,
Although what Carl has suggested is all good information, the "M" in DSL's "SM" series refers to "molded", those three dimensional horn curves are made from material injected in a mold, not bent or routed to shape.
As far as I recall, DSL does not use any curved enclosure walls, other than corner routing/sanding.
Art
The SM-LPM appears to have the back and bottom walls joined by a curve (with flat end caps), in addition to the molded horn.
Although I did establish earlier in this post that Marcel wanted to build curved enclosure walls, I think the original Danley link was something of a red herring...