Plan to - Planot ?

[GlidingDutchman]

Any ideas on this? Looks quite simple to build with a pair of busted harddisk drives and a few aluminum pieces...

www.planotspeaker.com

I already have an idea of doing a "diapraghm" from a prism frame covered with mylar film...

GD

[Jelle Schrijver]

Already build a prototype by myself. Problem with HDD is that the resonate a lot. Solid core is better then a hollow core. 2 reasons; 1) the walls of the hollow core tends to vibrate and start generating there own sound. 2) inertia, the weight central points moves outwards and that harms impuls.

Have developed a theory on why it works. John @ Planot wasn't interested strangely enough. I am looking for people with avionics skills to help design the perfect diagram rotor.

For the motor, my advice would be: Find 2 identical HDD, cut out the coil of the head. (so you have 2 identical coils). get 2 bar magnets. Place one in the center of the driving rod. Other one across it to act as a center (like the planot does). No place the 2 coils (fixed) to the sides of the magnet and wire them parallel, but so that when first coils emits N the other coil emits S. The coils are placed straight across each other with the rod + magnet in between. Coils of HDD head s are around 13 ohm's, so parallel will load your amp around 6 ohm's.

Benefit:

1)You could wind your own coils with heavy gauge wire, the don't move any more, so weight is not an issue. You create this way indestructible voicecoils
2) No more moving lead wires to the diagram. If pushed to hard, the diagram would simply make a complete turn and no harm is done.

And that center magnet is really needed! Unless you want to create a tweeter only! No centering, and it losses mids and lows.

About the diagram rotor, don't be afraid to go large. My 1 cm cross section rotor didn't reach low that well, but highs where past 17 khz. Because of the "middelpuntvliedende kracht" (sorry, don't know the english term) mass isn't a big influence on rotation frequencies.
Also in a prototype with X wings, the sound output dropped to about zero, so the angle of attack on the air has an optimum, the triangle shape pushing the angle that still works.

Planning to start construction on a bigger rotor very soon. Bigger means longer and a wider cross section.

Have you already build a prototype?

The sound is very adictive btw

[Ziggy]

Oh no.................here we go again