Technical FAQ

Home cinema - what is that?

While a hi-fi system consists of a sound source, amplifier and two loudspeakers, a home cinema installation adds more than just the film; for cinema or surround sound is provided by at least five loudspeakers. The left and right front speakers can be compared to those of a hi-fi system, but they are not completely identical.

In a home cinema arrangement, the front speakers are assisted by a center speaker, which is placed near the screen and mainly responsible for reproducing dialogue. However, good quality surround sound also requires two rear speakers located to the left and right adjacent to or behind the viewing position.

When using smaller front satellites in particular, use of a subwoofer is recommended. This provides the proper low-frequency foundation for exciting film sequences.

The positioning of surround sound loudspeakers

The center speaker should be positioned near the television, preferably above or below the screen. The magnetic shielding of the center speaker prevents distortion of the television picture.

Rear satellites, on the other hand, are positioned behind or, if that is not possible, next to the viewing position. They are best set up slightly above the level of the viewer's ears, i.e. 1 m above the floor, or a little higher. This means you will require stands if the speakers cannot be mounted on the wall or placed on a shelf. Incidentally, dipole and bipolar rear speakers broadcast the sound to the front and the rear, and so create a particularly spacious soundscape.

If a precise bass is important to you, then make sure all speakers are situated about 50 cm from the walls (if necessary from the floor too). In addition, the distance from viewing position to subwoofer and front speakers should be more or less equal.

To achieve maximum bass level, place the subwoofer near a wall or even in the corner. Reflections and stationary waves in the room can thus certainly double the volume of the bass - but transient and decay effects are prolonged to an extreme.

Dolby Surround, Dolby Digital - what is that?

Dolby Surround, or Dolby Pro-Logic, is a four-channel analogue technique which became established in the 1970s, firstly in cinemas, then in the home. It requires only two audio channels to store the information. Center and rear channels are added to the two front channels in coded form and contain neither low nor very high frequencies. For reproduction, Dolby Pro-Logic requires a corresponding decoder and merely a four-channel surround amplifier because both rear speakers carry the same signals. The feature films made in the 1970s and 1980s can also be received in Dolby Surround via a television.

Dolby Digital, or AC 3, on the other hand is a real five or six-channel technique (also known as 5.1) which only became popular in the 1990s. All five surround channels are completely independent of each other and also contain the lowest and highest frequencies. Therefore, Dolby Digital places higher demands on the center and rear speakers. The sixth channel contains only the very lowest frequencies and is connected to the digital surround amplifier via a separate subwoofer output. However, this channel can also be wired into the front channels or all five surround channels.

The five-channel "dts" delivers similar results to AC 3; however, it requires a different or additional decoder. Up to now, digital surround sound has only been available from digital versatile discs (DVD) or the German television broadcaster Pro7.

quadral - the correct loudspeaker for every requirement

As recently as 25 years ago, the loudspeaker world was rather a simple one; multi-channel sound was only available in the cinema, whilst at home, stereo reproduction of music was provided by two hifi boxes. The world of entertainment electronics has changed, however; the loudspeaker of former times has become a highly flexible multi-channel instrument for the reproduction of film sound and of pure music. In addition, the purchaser of today expects elegant, highly finished sound transducers which simultaneously offer excellent acoustic performance.

Nevertheless, not everybody is prepared to allocate loudspeakers a lot of space in the studio or living room. Instead, the boxes must be small and smart and still provide a sound which is dynamic, clear and multifarious, in short, "grown up". Apart from the size of the studio, there is also the question of personal priorities, of decision about box size and price level. Depending on whether one prefers the finest quality music reproduction from audio DVD and SACD or whether one only occasionally plays a CD or a DVD video disc to fill one's leisure time, it should be remembered that apart from the acoustics of a room, it is the quality of the loudspeakers which most strongly influences the overall sound picture. In a certain respect the purchase of a loudspeaker appears very difficult, but you will find that with the help of our website, the identification of the best loudspeaker combination to meet your expectations is a relatively simple task.

If, for example, you want to "wire for sound" a small to medium-sized room (up to 30 sq. metres) and regard an as far as possible visually unnoticeable  installation of equipment as important, we would recommend our complete SURROUND series systems with compact, classically designed satellites. The 5.1- process of current multi-channel sound technology will enable you to experience effects of every kind, as though you were actually present and if you wish to use your system to reproduce the new Extended Surround Dolby Digital 5.1 EX and DTS ES Discrete/Matrix 6.1 sound formats, quadrals variable MAXI Line with individual satellites of different size, is available. MAXI is excellently suited for building up a wholly individual Surround installation; whether 5.1, 6.1 or 7.1 and here you are at the control console and can assemble your own personal favourites. Naturally, a Sub-/ Sat system also requires a suitable subwoofer, for example in order to generate a low frequency "rolling thunder" and for this purpose we have available a range of active high performance "basses" to enhance your personal multi-channel experience.

The present trend is for slim, smart loudspeakers. In order to also meet authentic 5.1-, 6.1- or 7.1 reproduction requirements, we have created ALUMA, handsome, slim satellites available in various sizes and with different combination options, highly loadable, carefully constructed and also able to be used in large rooms of up to 50 sq. metres. They are also supplemented by a subwoofer. You get to hear a great deal from MAXI and ALUMA, but only to see very little, because the compact housings fit harmoniously into any living ambiance and what is visible can really be seen in the truest sense of the word, namely, an elegant, timelessly styled solid aluminium housings.

There are nevertheless also listeners, who want loudspeakers to be recognisable as such as part of the studio, on which they confer an elegant technical air and a technology which is visible, audible and last but not least, affordable, in short, who want a lot of sound and high quality of material for their money. For this we recommend the quadrals ARGENTUM series characterised by a particularly favourable price/performance ratio. It does not matter whether you wish mainly to enjoy films, or whether you are a music lover; ARGENTUM will satisfy both these needs equally well.

Are you looking for a loudspeaker with a high gloss lacquer housing, excellent sound characteristics and fairly priced? If so, our PLATINUM series is exactly right for you. Being a keen stereo listener, do you resort to one of the three-stand or two sound-intensive shelf loudspeakers, or if you wish to have "multi-channel" immediately, one of the PLATINUM complete sets, whose components fit perfectly with one another? All PLATINUM loudspeakers will enable you to enhance your personal sound experience via an active subwoofer chosen from our highly serviceable product range.

There are connoisseurs who wish to hear every musical detail, the dying sounds of the piano and the soft tones of the cello and to be able to do so in stereo and multi-channel technology. When listening to a film, do you wish to hear not only the overall impressive sound, but also the fine modelling of small side-effects such as the stirring of branches, the restless murmur of a stream, the vivacious twittering of birds in the crowns of trees and all of this from sound devices of timeless elegance. At quadral we have the answer to all these wants, namely, the CHROMIUM STLYE series, housed in high gloss lacquered cabinet and handsome form, perfect acoustics and option-related flexibility, suitable for practically any studio and the active subwoofer SUB 88 impressively underscoring the sound picture with a precise room-filling bass.

But perhaps you would like even more, namely, the peak of what is technically feasible; in that case we recommend our AURUM build-up series, to enable you to understand the loudspeaker as a total technical and visual work of art implementing an artefact with the highest degree of care and to become acquainted with details which you did not know before . This is AURUM, quadrals High End series for listeners with top requirements, characterised by the finest materials and premium processing, representing a new dimension; In its listening ambiance AURUM represents a perfect synthesis of strength and finesse, dynamics and plasticity, as if made not only for CD's and video DVD's, but also for high quality audio DVD and SACD tone formats, since AURUM loudspeakers make every detail come to life, perhaps even some finer points which you never noticed before and your guests will be astonished that not only your top-quality furniture, but also your new loudspeakers, are a dream in terms of both appearance and of performance.

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.

Stereo, Surround or both? quadral offers tailor-made solutions.

Whether you want to enjoy CDs or normal discs in hifi-stereo, whether an extensive sound film experience is more important to you, or whether you want to listen to audio DVD's and SACD's in High End quality, quadral loudspeakers make everything possible.

For the lover of excellent stereo reproduction and of detail, a floorstand loudspeaker offers acoustically the best solution. All our floorstand boxes of the ARGENTUM, CHROMIUM STYLE, PLATINUM and AURUM series are fitted with a solid basic base and multifarious harmonic tone reproduction, which is essential for maximum enjoyment of music. Smaller and less forceful in low bass are our shelf loudspeakers. In all cases the use of high-grade materials and the durable mature and correct construction is typical of quadral.

Are you price-conscious and fond of a technically clear and unencumbered form? If so, you will find our ARGENTUM series exactly right. Do you value classically elegant appearance and a dynamic presence even in a large living room ? If so, you will be enthusiastic about our PLATINUM series; for the highest requirements of sound and finish we have created our AURUM series and in the foreground the premium stand-mounted models AURUM TITAN, AURUM VULKAN and AURUM MONTAN.

Are you first and foremost a hifi listener, but would you also occasionally like to view a Surround film ? If so, there is no problem, since all our loudspeakers have available an suitable Centre and Surround loudspeaker, matching one another both acoustically and visually. It does not matter whether you want to watch Verdi's "Aida" or Cameron's "Titanic", quadral loudspeakers will place you acoustically at the centre of the event.

If you should want to reproduce first-class audio DVD and SACD recordings of outstanding multi-channel quality, our top quality loudspeakers of the AURUM and CHROMIUM STYLE series afford every refinement, every detail perfectly incorporated into a multi-layer, differentiated sound picture. CHROMIUM STLYE was originally and specifically designed for combining outstanding appearance with very good DVD reproduction, but was later optimised for pure media such as CD's and audio DVD's.

Your DVD shelf always contains the latest blockbuster from Hollywood. Do you like to arrange film evenings for your friends? Do you like intensive surround reproduction with crystal-clear harmonics and profound basses? Perhaps you even prefer to listen to your CD's via Dolby Pro Logic 2 to involve your entire box system. If so, we offer ALUMA and MAXI, which are exactly the right loudspeakers for you. Compact, timelessly elegant aluminium loudspeakers, which confer an absolutely authentic air on films when the DVD is played on the most recent Extended Surround sound formats; for the deepest tone positions we recommend the subwoofers specifically created for this purpose by quadral.

Is your studio rather small and you want TV broadcasts and DVD films to be as intensive as possible with full sound on all sides? For this, too, we have the right solution, quadrals SURROUND complete systems, modest as to space requirement, but room-filling as to sound.

DVD Audio and SACD for highest musical enjoymen

Audio DVD's and SACD's improve, in particular, the reproduction of harmonics, which in the opinion of insiders, sound emotionless and not very natural on video DVD's and CD's. In the area of high tones both these new media reach far above frequencies, which are stil audible to the human ear in the form of pure sinus tones (approximately 15 to 20 kHz). Nevertheless, very high harmonics contribute to the overall sound. The new high-resolution tone formats are much more suitable for faithful reproduction of the original including all harmonics, than, for example, existing CD's with their much smaller frequency spectrum.

A further advantage of audio DVD resides in the fact that it makes available up to seven separate channels at the highest sound level.. Whilst the video DVD is also surround-capable, it calls for the lion's share of its capacity for the film, instead of for sound reproduction and does not nearly attain the high sound level of its younger sister. The excellent sound of the SACD is also surround-capable, whilst the CD continues to be satisfied with two channels. Many SACD's are even double-layer branded (hybrid process), so that normal CD players can play them in stereo. It can be asserted that only audio DVD and the more recent SACD recordings afford maximum listening pleasure.

Both the new audio formats offer a big challenge to loudspeakers on the reproduction of harmonics so as to be able to make real use of the aforementioned sound advantages of  audio  DVD's and SACD's. In this connection it is not really important to extend the loudspeaker frequency range to over 50 kHz, but rather the existing resolution capacity, which makes an ambitious audio DVD or SACD recording a special sound event.

Almost ideal for these purposes is the quadrals RiCom M high tweeter, with its flexural resonator membrane, which, in contrast with piston-type transducers (e.g calottes) needs to move a lesser mass of air in front of it in order to create sound. Due to its flexible silk texture membrane, the RiCom M can be used down to the middle tone area, where it produces music much more easily, but also spreads at a much wider angle than a bigger and heavier middle tone membrane. At the top, its frequency range only ends at 60 kHz. All loudspeakers of the AURUM series arte distinguished by the fantastic quadrals RiCom M high tweeter.

Not quite so broadband, but also high resolution and closely related to the RiCom M high tweeter is the quadral aluminium calotte, which has been optimised by painstaking work lasting two years. It assists ARGENTUM loudspeakers to give very fine performance in the high frequency area and also makes them into impressive play partners of SACD's and audio DVD's.

Thanks to the detail-loving quadral Altima® membranes for low to middle frequencies, quadral AURUM loudspeakers provide an incomparable musical experience, where everything is right, from the smallest detail up to a magnificent harmony.

How does a pressure chamber reflex principle work?

The big floor-standing speakers such as AURUM’s TITAN, VULKAN, MONTAN, ORKAN and also the quadral PLATINUM M50 and M40 are constructed and engineered cabinets that utilise a pressure chamber reflex principle. The rear of the speaker membrane works under the principle of bass reflex volume whilst the front surface of the speaker membrane works on the principle of a pressure chamber. This technique derives originally from professional studio monitors and is almost unequalled in HiFi loudspeakers. The combination of a pressure chamber and the reflex principle together enables an extensive depth coupled with the very highest precision, and, even at very high levels of being driven, the bass stays true, contoured and sublime.