Modeling the Bang & Olufsen Beosound A1 Speaker Grill: Rhino, Grasshopper & KeyShot Workflow

The Bang & Olufsen Beosound A1 is renowned for its organic, seamlessly perforated aluminum dome. Replicating this signature pattern manually in CAD can be tedious, but leveraging Rhinoceros 3D, Grasshopper, and KeyShot allows for a parametric, non-destructive modeling workflow.

Download File

Here is the step-by-step workflow to generate the double-curved perforation texture and render the final model.

1.Model Base Geometry in Rhinoceros 3D:Set up cleanest surfaces for projection.

• Draft Profile Curves: In your Front or Right viewport, trace the reference profile of the Beosound A1. Create two distinct curves: one for the top aluminum dome and one for the polymer base.
• Revolve Surfaces: Select the dome profile curve, run the Revolve command, and set the revolution axis to 0,0,0 vertically (Z-Axis). Repeat for the bottom shell.
• Organize Layers: Place the top dome onto a designated Base Surface layer. Keeping this surface trimmed and clean ensures Grasshopper projects curves without errors.

2.Generate Perforation Grid in Grasshopper 3D:Parametric curve projection and arraying.

• Extract & Divide Base Curves: Bring the target dome surface into Grasshopper via a Surface parameter. Sample a guide curve along the surface contour and use Divide Distance or Divide Length to generate equidistant points.
• Extrude & Project: Extrude directional vector lines from these points using Line SDL and project them onto the main dome geometry using the Project component.
• Rotate & Intersect: Use the Rotate component to spin the projected curve set by 120° around the central vertical axis. Find the intersection points using Curve | Curve (CCX) to build an equilateral triangular lattice layout across the dome.
• Perforation Pattern: Construct Planes Normal to the surface at every intersection point. Place Circle components onto these planes to define hole diameters. Use Surface Split or Region Difference to punch the perforations cleanly into the main dome surface.

3.Render & Refine in KeyShot:LiveLink synchronization and micro-filleting.

• Export via LiveLink: Send the geometry to KeyShot using the Rhino to KeyShot LiveLink plugin to retain layer structures and materials.
• Environment & Lighting: Set up a studio environment with warm directional HDRI highlights to emphasize the metallic curvature of the dome.
• Apply Micro-Fillets: Select the perforated dome geometry in KeyShot, navigate to the Project > Scene > Model Properties tab, and add a subtle Micro-Fillet (e.g., 0.2 mm). This rounds off sharp CAD edges and creates realistic light highlights on every perforation edge.
• Iterate Density: Adjust point counts or circle radii in Grasshopper and click Update in the Rhino LiveLink toolbar to push changes directly into KeyShot without resetting materials.

Key Modeling Takeaways

• Equidistant Spacing: Using 120° rotational symmetry ensures the hole pattern stays uniform along the double-curved surface without distortion.
• Render-Time Edge Softening: Instead of filleting thousands of holes inside CAD—which inflates file size—let KeyShot's Micro-Fillet handle soft edges at render time to optimize performance.

‍