dougi
Addicted to Fun and Learning
I recently purchased a pair of Elipson Planet Ls and again some Planet Ms. I got some for great prices and wanted to add surrounds that would be permitted by the wife.
The Ls do look very nice in Mercury Ice on the dedicated floor stands!

Given they are both concentric driver speakers I thought I would do some quick measurements to see what they were like.
Note that these were done on the stands at 0.5m. While I didn't gate the measurements I guess they are "semi-quasi anechoic" given the distance removes enough of the room to see what is going on and, being, concentric, you can measure close.
Below are for the Planet L including bodged Spinorama based on only three measurements. Given the speakers are spherical, you can reasonably extrapolate them with a bit of license.





It has a slightly rising response, bad resonance/absorption in the top octave and bass down to 55 Hz or so. Directivity, as expected given coaxial, is good apart from what on earth is going on in the top octave, which the grill makes worse. Distortion (at 84dBSPL@1m equivalent) is OK. Lucky I don't have any hearing left in the top octave. Elipson spec is +-3dB 48 Hz-20 kHz. Maybe with a bit of squinting! (note grill measurement made at a different time in a slightly different location so the bass is a bit different)
Below are the same for the much small Planet Ms.




Apart from the complete lack of bass probably a bit nicer with smoother directivity. Response is quoted at 90 Hz - 22kHz +-3dB. Again this is stretch with 90 Hz being about the -10dB point.
In summary, the Planet L looks a flawed design with the issues in the top octave. The Polish site test certainly picked up the same. In the REW spectrogram plot you can see the stored energy at 10kHz easily. I assume this is due to something in the coaxial driver design. I can't give listening comments as I haven't really listened to either of them. They perform OK with the Ls as surrounds and Ms as Atmos elevation (for all the good they seem to do).
The Ls do look very nice in Mercury Ice on the dedicated floor stands!

Given they are both concentric driver speakers I thought I would do some quick measurements to see what they were like.
Note that these were done on the stands at 0.5m. While I didn't gate the measurements I guess they are "semi-quasi anechoic" given the distance removes enough of the room to see what is going on and, being, concentric, you can measure close.
Below are for the Planet L including bodged Spinorama based on only three measurements. Given the speakers are spherical, you can reasonably extrapolate them with a bit of license.





It has a slightly rising response, bad resonance/absorption in the top octave and bass down to 55 Hz or so. Directivity, as expected given coaxial, is good apart from what on earth is going on in the top octave, which the grill makes worse. Distortion (at 84dBSPL@1m equivalent) is OK. Lucky I don't have any hearing left in the top octave. Elipson spec is +-3dB 48 Hz-20 kHz. Maybe with a bit of squinting! (note grill measurement made at a different time in a slightly different location so the bass is a bit different)
Below are the same for the much small Planet Ms.




Apart from the complete lack of bass probably a bit nicer with smoother directivity. Response is quoted at 90 Hz - 22kHz +-3dB. Again this is stretch with 90 Hz being about the -10dB point.
In summary, the Planet L looks a flawed design with the issues in the top octave. The Polish site test certainly picked up the same. In the REW spectrogram plot you can see the stored energy at 10kHz easily. I assume this is due to something in the coaxial driver design. I can't give listening comments as I haven't really listened to either of them. They perform OK with the Ls as surrounds and Ms as Atmos elevation (for all the good they seem to do).