А технология новых Утопий, это не то?

http://www.grande-utopia-em.com/en/technologies/em.php

Electro-Magnetic EM
The expected great technological step in the bass is reached with the 153/4” (40cm) woofer with an
electro-magnetic motor. The principle: the permanent magnet is replaced by an electro-magnet. Thus the
magnet force can become endless – or flexible. Just one figure: the woofer Force Factor of the previous
Grande Utopia Be reached the respectable figure of 18.5T.m, it now goes to 34T.m, that’s to say an 83%
progress. A figure that foretells a spate of others: the field in the air gap reaches 1.75T, the efficiency
97dB/1W/1m, that’s to say a sensitivity superior to 100dB for 2.83V. These figures can make you wonder
concerning the dynamic bandwidth but moreover when we combine them to its resonance frequency:
23.8Hz, that’s to say an almost “unusually” low value, considering the reached efficiency. Because, so far,
we had to choose between the two: high efficiency or ability to go down in the low frequencies, until we
reached the right proportioning, and that was an acceptable compromise.
The choice of the EM technology is the clear consequence of the absence of any compromise: we wanted
a superlative woofer, which was not possible with the classic magnet technologies. We called on
an ancient technology that had been dropped out because it was too complex, able to reach extreme
performance: the electromagnet. A technology that we improved thanks to the simulation software of the
magnetic motors and high-performance modern materials. In the end, the electro-magnet uses no less than
15.4lb (7kg) of copper, for a 48.5lb (22kg) motor and a total weight of 52.9lb (24kg). A “monster”, in the
literal meaning of the word, which manufacturing costs cannot be compared to a standard magnet and are
only conceivable on exceptional loudspeakers.
The electro-magnet power supply is external and has a signal recognition system. It offers above all an
adjustment of the power supply tension on 6 levels (for a delivered power from 9W to 90W). So that’s
the choice of a complete sound range for the bass, deep and round, or punchy with a “live” sound, and 4
intermediate levels to program a flexible bass sound. These adjustments permit to ensure a control of the
bass without precedent, keeping control of the speaker / listening room coupling (making the over-voltage
coefficient vary but also the efficiency on a +/-3dB scale).