Rotary Speaker - isolation cabinet

Rotary Speaker - isolation cabinet - Part 3

Part 3

A lot of my projects end up in the living room so I typically try to make them part of the 'furniture and fittings' and I tend to have a 'Fisher-Price' approach to interior decor - colourful/playful.

The wood I'd used for the isolation cabinet were off-cuts, leftovers and recycled bits, which were all fairly rough so I filled the worst of the old screw holes, scrapes and nicks with dowels and filler.

However, I didn't have the energy, time or enthusiasm for marathon sanding to achieve a smooth finish. Instead, I went with a plaster medium paint which I applied with a roller. This filled and covered over the remaining imperfections reasonably well to leave a nice textured surface.

I then painted the two parts - blue for the upper section, beige below, followed by a few coats of water based varnish and was pleased with end result.

I added some wooden handles to the upper section so that it can be easily lifted off and put back on as needed. Without these, the weight and flush fit made it a struggle to remove.

There are 3 sets of cables running in/out of the cabinet: 2 each for the speaker, motor and microphone. I decided that using a 9-pin D-sub connector was the most practical since I can connect the cabinet to the controller box (details to follow in a later post) without multiple wires all over the place and I already have various lengths of 9 pin cables - ranging up to 5 metres.

In these final images, you can hopefully see how it all fits together around the rotor.

The microphone here has a wind shield (the red foam) since the spinning rotor creates enough of a draft to cause a slight 'popping' sound. If the microphone were a little further away, this wouldn't be an issue but the dimensions here don't allow that. The microphone is attached to a plastic tube inserted into a rubber grommet (yellow). This arrangement dampens any vibrations while also allowing adjustments to the microphone position.

In terms of stopping sound to the outside world the cabinet is very effective. This video demonstrates just how much it can reduce the volume:

In the next part, I'll show the control box and hopefully demonstrate sounds from the internal microphone.

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Yamaha PS-30 : Solo Section Filter and De-tune Mods

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Lord of the Hertz

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