The project has been canceled.

This is not because it is a bad design. The original Pluto is really a good speaker and it has taught me a whole lot.
But many further thoughts about it have resulted in Kierkegaard while many other thoughts went into Demokrit-T. So I have two speakers, one of which has a higher directivity also vertically and one has a lower directivity. In both cases the off-axis behavior is as good and smooth as can be. And Kierkegaard demonstrates even a better horizontal and vertical off-axis behavior although it is a speaker with a rather conventional box.
These facts simply make Platon redundant.
While the subs were optional to Platon, they are required for Kierkegaard. But I would have gone for a pair anyway because a proper low end adds significant value to the reproduction.

In history Platon was there before Aristoteles. Actually, Platon was his teacher. For me closed box designs were also there before dipoles and I consider closed boxes the older teachings.

Platon is a fully active closed box with omni directional behavior over a wide frequency range. It is obvious that this speaker was inspired by the Linkwitz Pluto. The picture shows the test balloon that I have put together to compare it to Aristoteles. So far I can tell that the Peerless 2" FR does a good job and I plan to keep it. The choice for the mid-woofer has now been made. It will be the L16RN-SL (H1480). Especially when used without sub woofer(s), it is still the best driver for this application and a very nice unit indeed. Even much more expensive drivers are not so well suited.
The audible impression is very believable but with less depth of the sound stage compared to Aristoteles. It is planned to design a sub woofer for it.

Primary Design Goals:

  • Smooth transition from omni to forward firing behavior (compared to Pluto the directivity index will rise above 17KHz because the Peerless actually reaches that far. But only on axis).



Status of the project:

  • 11-Jun-2011: Comparison between Peerless and Aurasound driver of Pluto conducted (see measurement section).

The driver has a very good value for the money and can be used in a variety of applications. It is nearly as esthetically as the ScanSpeak units I have. The long lead wires were initially nearly shorted underneath the aluminum membrane and needed to be bent carefully a little towards the sides.

Last updated 03-Feb-2019