So, now we have the first complete measurements of the LXmini and the results are very interesting - to keep the post from becoming page long, just a few notes....
In two posts (see
here and
here) I tried to analyze the LXmini a bit based on S. Linkwitz (SL) original measurements. Some things are confirmed by
Erin's measurements, others differ strongly.
Comparison on-axis measurement SL and Erin's Klippel
Both measurements use the center of the 4'' full-range driver as the measurement axis. The measurement of SL was probably made at 1m distance, the Klippel measurement calculated at 2m distance. Because of the small distances of the drivers, the different measuring distances has nearly no influence on the shape of the on-axis FR.
Therefore, the differences in frequency response are astonishing:
View attachment 222054
I don't know if SL made any drastic changes after his published measurements, but the 3dB differences in the 1.8-4kHz range are dramatic sound-wise.
If a PEQ is set in the MiniDSP in the range around 10-16kHz, it should be checked - it seems that the break-up frequency of the driver is not hit cleanly.
The Youtube comments on Erin's video say that some find the speaker harsh in certain frequency ranges.
This could have something to do with the somewhat too present 2-5kHz range that Erin's on-axis measurements show - in SL's measurements, this range was lowered 3dB.
This is reflected in the performance of the ER, SP and PIR.
PIR:
View attachment 222056
"The response in the vertical plane should be similar, because of closeness of the acoustically small sources"
This
quote from SL with regard to the LXmini is true on the whole, but rather not in detail.
Horizontally and vertically, you can observe a kind of dipolar radiation behavior ("hypercardioid") in the range of 1-8kHz. However, the vertical radiation has additional side lobes (see pink ellipses). Mainly due to the upward radiating driver. The hypercardioid radiation and the side lobes could be the explanation for the huge sound stage that many hear.
View attachment 222077
This also results in a lot of sound energy being emitted in the vertical range 30-60° (see purple ellipse) - which can be easily seen in the unusual slope of the "ceiling bounce" in the early reflections diagram.
View attachment 222078
The result is a significant increase in the sound power output in the range 400-1000Hz - can be seen in the above PIR graph. Whether this has an effect on the sound is difficult to say (speculation based on the measurements: possibly the LS could sometimes sound a little tinny, nasal or not).
The "problem" of the increased sound power output only becomes really visible when the vertical measurements are included and can easily be overlooked if only the horizontal FR are considered.
It is not surprising that such an LS does not tolerate high SPL levels (sealed speaker and 4'' mid-high) and is confirmed by high multi-tone distortion - but high SPL is not the goal of the LS.