Three years ago, while visiting Acapella’s showroom in Duisburg, I experienced that a Poseydon could bring you closer to the dynamics of a concert event than even the most demanding hi-fi enthusiast could have ever dreamed of. And, the acoustic transducer currently being there in demonstration, is intended to narrow the gap between reality and illusion even more. And you can listen to it by yourself!

In the meantime, a lot has happened at Acapella Audio Arts: Besides Hermann Winters and Alfred Rudolph, also his sons Robert and Richard are now part of the team, while the legal structure of the company has changed accordingly. Richard Rudolph has now been involved in research and production for well over ten years and with the current Sphäron Excalibur he has played a decisive role in the further development of Acapella's top model. Understandably, these systems are only built to order, incorporating the latest insights from the constant quest for a continuously improving performance. In contrast to the early Sphäron models, the current system does not require a bass horn acoustically coupling to the room anymore. While for the earlier solution a horn area of twelve square meters was indispensable, the current model shows up with modular, more than head-high bass columns. Each of the four modules following the vented enclosure principle, features an 18-inch driver.

The system also includes Acapella’s proprietary mono power amplifiers, derived from their integrated amplifier LaMusika and their three-phase powered stereo power amplifier. However, there is "only" one mono block per channel, integrated in the speaker cabinet on a suspended base. The assignment of the frequencies to the woofer modules, the low-midrange and high-midrange horns as well as to the ion tweeter is effected by a passive crossover. When asked about the power rating of the power amplifier, Hermann Winters answers – almost as expected – in the classic manner very much known from Rolls Royce: perfectly adequate. Technical questions he simply considers to be inappropriate: They don’t reveal anything about the sonic properties and the musicality of this exceptional speaker system. Whereas he willingly quenches the thirst for knowledge related to the system’s weight, although, before it comes to transport, this question can’t clearly be answered: A Sphäron isn’t something you simply lift onto a balance. The estimated weight ranges between 650 and 750 kilograms per side.

A direct comparison between the Sphäron and the Poseydon, which impressed me so positively on my last visit, won’t be realizable, as the Acapella team dismantled it to make room in the generously dimensioned listening room for the new things to come. But, a snappy comparison certainly would not do the Sphäron Excalibur justice. Already the first track, a song by Nils Lofgren, with which Richard Rudolph starts the audition, unveils: it’s instantly powerful and impressive, but also bigger than live. However, I don’t know if it was because Richard Rudolph minimally reduced the volume or if I, as usual, had closed my eyes for focused listening: Suddenly the proportions snap in. While the imaginary stage charms with its spaciousness, the enormously differentiated instruments and voices perform in an absolutely harmonious and dimensionally lifelike manner, letting you indulge fully relaxed in a wealth of information. Already this first song – being up to now unknown to me and technically not necessarily an audiophile masterpiece – gives rise to my worst fears: If I do not stop being captivated by the Sphäron Excalibur right now, I will never be able to listen to music through my own system as satisfied as before.