5) Extended Surround: Find out what happens behind your back!

Many multi-channel solutions for film and music reproduction work on the 5.1 principle. Used for this purpose are five full-range channels and an additional bass channel with two main and one centre loudspeaker in front and two surround boxes for all-suround effects at the back. Point one (.1) refers to the bass channel able to be reproduced by active subwoofers with built-in amplifiers.

The 5.1 systems use only one centre loudspeaker for voice reproduction and other signals which should be located in front centre. In the case of 5.1, no centre is provided behind the listener. Dolby and dts technicians ended this lack long ago by means of the "Extended Surround". Dolby (Dolby Digital 6.1 EX) generates the signal for a rear centre by the matrix process from the left and right rear channel, but the frequency range of this rear centre is nevertheless limited. The dts competition has developed, apart from a similar version (dts ES Matrix 6.1) also an Extended Surround design, where an additional full range channel is available for the rear centre (dts ES discrete). The dts ES discrete even has two rear centres called  "surround back speakers" and is therefore also called the 7.1 process. Nevertheless, dts ES discrete calls for six-channel sound recordings plus a bass channel, whilst the matrix process makes do with the normal 5.1 recordings.

The Extended Surround processes facilitate, on the one hand, the location of effects coming centrally from the rear and on the other hand, a convincing all-round effect is achieved, if one is not sitting in the middle among all the loudspeakers. This nevertheless requires an AV amplifier/receiver complying with the technical conditions for Extended Surround reproduction and also the corresponding number of suitable loudspeakers. Extended Surround provides a home cinema experience such as is only found in few high-tech cinemas and only with Extended Surround you can find out what happens behind your back. In addition, quadral enables loudspeakers to be almost invisible, in order to maintain the aesthetic of your individual living environment

For this purpose our flexible, compact and highly loadable MAXI series offers satellites of different sizes, in order to enable you to build up a Surround installation meeting your own personal ideas. MAXI even complies fully the acoustic ideal of a 6.1 or 7.1 configuration, since you can introduce the same box six or seven times. That way you obtain a precise, all round distributed and particularly homogeneous sound picture. If in addition you also place all loudspeakers at the same height, you will obtain an acoustic performance, which can hardly be improved on in terms of consistency and conviction  Even if you wish to start with a stereo solution, there is no problem; MAXI's can also be later extended to a 7.1 installation.

Extended Surround is very fine, with quadrals ALUMA series. Slim, progressively elegant sound columns with dynamic, differentiated reproduction, where every DVD becomes a visual and an acoustic delight. Our ALUMA loudspeakers generate a Surround sound environment with extensive space audibility and at the same time an immense quantity of detail, a true delight for both eye and ear. ALUMA also needs only a small amount of room and can be used for hifi-stereo up to Extended Surround.

It should be remembered that quadral offers a wide range of active subwoofers, which confer on the bass area supreme power of expression.