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reproduction of surround effects but also provides a remarkably deep and steady
bass. In other words, Jamo XBR combines the best of these two principles.
Because XBR carries out the electrical phase shift on one of the woofers, the
C 80 SUR are individually confi gured as a left and a right loudspeaker. In this way
the perfect interaction with the front speakers is achieved i.e. there’s a perfect tran-
sition between front and surround speakers when sound effects pan back and
forth across the room.
C 80 SUB
The C 80 motional feedback-controlled active subwoofer is equipped with two
very powerful 10in aluminium cone woofers in a closed cabinet.
The advantage of using two 10in woofers instead of one large one are two-fold.
One is higher power handling capability - as the heat is better disposed of in two
voice coils/magnet systems – and the other a faster attack - as a smaller woofer has
less moving mass and thus is better controlled. Finally the more compact resulting
design makes it a lot easier to fi nd a suitable area to place the subwoofer. The cone
area of the two 10in woofers equals the size of one 13in woofer.
The sub’s BASH® technology-based amplifi er delivers no less than 1800W – more
than enough to secure suffi cient headroom, even for a subwoofer reaching down
to 20Hz (- 6dB).
Amplifi er
The important thing with subwoofer amplifi ers is the ability to deliver high power,
something that’s especially important for the reproduction of peak bursts (e.g. an
explosion or a bass drum) with full fi delity. This has to be done with a minimum of
distortion and while maintaining very tight control over the woofer.
Due to the nature of a conventional class AB amplifi er it needs to have a substantial
supply since only approx 60% of the power is turned into sound – the rest is turned
into heat. Consequently the heat sink of a conventional amplifi er also has to be
enormous in order to cool it properly.
On the other hand a class AB amplifi er also has some excellent advantages, such as
musicality, low distortion and a high damping factor.
So, wouldn’t it be nice if we could combine these qualities with the effi ciency of a
Class D amplifi er?
That’s why the development team decided to turn to a specialized technology that
met those needs – one that delivered high power output with high effi ciency while
maintaining musicality, low distortion and tight control over the woofer. A patent-
ed technology called BASH®.
The key operating principle of BASH technology is based on a continually variable
