Questions to Acapella Celestron Delta 4 with Plasma Corona Ion Tweeter

This loudspeaker system from German's manufacturer Acapella is a 4 way version. The speaker utilizes 3 spherical wave horns.
The bass horn is presumably fitted with the Dynaudio 30W54, the midrange horn with the Dynaudio D54.
For the highs, the Corona Ion tweeter is used.
The horns are supported by a sepearate bass enclosure below 230 Hz. The bass enclosure is an infinite baffle system with four (roughly) 30cm/12" woofers each. The bass enclosure is 220cm/7'4" tall!
Pictures are here:
Hornlautsprechersystem ACAPELLA TRIOLON EXCALIBUR MK II (first image)
and
Dayton Wright Audio Links (sroll down)
The upper three ways must actually be the same than used by the Triolon - go to
Review Hornspeaker Acapella Triolon
The currently user want an additional IB subwoofer system similar to those from the first picture by post # about this thread:
Ultimate Solution for an User with already present "InWall" Subwoofer:ESL or dynamicL - diyAudio
and pictures from post 15 about
New Approach for an Outline from a DIY Subwoofer - Precision Devices PD2150 inside - Page 2 - diyAudio
First step before realizing a subwoofer project was to investigate the frequency responses from the lower three ways
to find out any anomalies. I create near field measurements and such at the listening place.
First question is, who know about meaningful measurements in test reviews of this loudspeaker of of the Triolon ?
Now the description to the three images of frequency response (I use DAAS3NT - go to the attached PDF in post #3):

First picture shows the nearfield measurements of frequency response from the lower three ways. Left curvature (blue) is those from the 220cm/7'4" tall bass enclosure (closed box, not vented box). the middle curvature (white) shows the large spherical wave horn with Dynaudio's 30W54 - and the right one (also white) those of the midrange spherical wave horn with Dynaudio's midrange dome D54. All three curvatures are from the left channel. Right channel provide the same results in the near field.

Second picture shows the response at the listening place from left channel (please ignore the yellow curvature) and the right channel at listening place shows the third picture. The different from left and right channel - particularly below 1 KHz comes from different conditions concerning the arrangement by installation: Right channel stands near by the right side wall in opposite to the left channel - the left side wall is far away.

The most the most striking detail is the wide band overlap of the first and second curvature from first picture so as the peak of the second curvature (30W54) which is in absence at listening place only at the right channel near the wall. What was here the goal from the developers ???
 

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First question is, who know about meaningful measurements in test reviews of this loudspeaker or of the Triolon ??
No advices?
Additional of interest for me is the fact, whether there are differences in the frequency response between the Celestron Delta 4 and the Triolon inside of the upper three ways.
 
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