|Product :||Beosystem 2500||
|Produced from :||1991 - Feb 1994|
|Designed by :||David Lewis|
|Finish :||Black / Aluminium|
The Beosystem 2500 was made up of a Beocenter 2500 and a pair of Beolab 2500 active loudspeakers. The whole system could be mounted on the wall using a specially-designed kit complete with carrying handles.
Bang & Olufsen invited design and audio journalists from all over Europe and the USA to a Modem Art gallery in Copenhagen at the end of November for the launch of an intriguing “new product concept”. This proved to be a compact three-piece system aimed at affluent “young metropolitans of the 1990s” in typically elegant and simple Art Deco inspired styling. The Beosystem 2500 is to cost about £1,995 and comprises a slimline music centre sloping back at 13 degrees from the vertical plus a pair of similarly sloping active loudspeakers. The centre unit contains a dual 16-bit, four-times oversampling CD player, an auto-reverse cassette deck and an AM/FM radio plus clock and record/start-up timer operation (if used with the Beolink 5000). These are arranged around a central control panel with versatile displays located behind tinted glass doors. The latter are described as “open sesame” doors because, as soon as one’s hand comes within 10cm, they glide open and the inner lights come on. Then, 15 seconds after the last control has been touched, the doors close silently and the lights are dimmed. The tuner section has 20 preset stations on each of the FM and AM bands, and there is an optional RDS kit to provide station name displays and auto-tuning.
The loudspeakers are extremely slim and only 3 litres in net internal volume, yet they contain separate 70W amplifiers for treble and bass tailored to give low-distortion reproduction all the way up to a very loud 109dB. Speaker grilles in six attractive colours allow chameleon-like changes to suit the particular room décor.
A rigid channel conceals all cables and an optional bracket with carrying handles facilitates a shift from room to room. The total weight, however, is 20kg and so the system is best described as semi-portable although it is certainly very flexible in terms of placement on a shelf or room-divider anywhere in the home. Alternatively, wall mounting is possible and of course the Beosystem 2500 can be coupled to a B&O Beolink multiroom installation. The centre unit measures 32 x 36 x 16cm and adding the loudspeakers increases the width to 83cm.
Taken from ‘Gramophone’ magazine - Feb 1991 (page 140)
LIKE so many Scandinavians, everybody who works at Bang & Olufsen seems to put good design, allied to clean modem styling, at the top of their list of priorities. You get the feeling that an ugly piece of hi-fl, however delectable it sounded, would never be given house-room. Each new item of B&O audio or television equipment bears this out. It may do the same job as countless rival products but it aspires to standards of aesthetics and functionalism (in short, artistic design) which make it stand out from the rest. To merit houseroom in a modem home of the 1990s, it should take up no more space than is absolutely necessary yet must provide above-average performance and convenience.
This new Beosystem 2500 carries the B&O philosophy to extreme lengths. The eye-catching, art déco-inspired design was actually the work of a British member of the B&O team, but he has lived in Denmark so long that I think we must have lost him for good. One design brief seems to have been the achievement of minimal external dimensions, and indeed this complete ‘plug in and switch on’ music centre, with its detachable loudspeakers, has been shrunk almost to portable radio-cassette proportions despite its genuinely high fidelity performance.
In one way this works to B&O’s disadvantage in that the perceived value for money at first glance is not too great. I can imagine shoppers feeling that the system does not offer very much hardware for the admittedly up-market price of 1,995 GBP. Closer inspection is needed to unveil the numerous operational plus points, and listening to the surprisingly open and powerful sound may be the only way for any intending purchaser to be persuaded that this compact system—capable of being lifted and moved to places where you might not expect to set up a hi-fl system—is indeed well worth the asking price.
The central unit is packed with ‘hi-tech’ innovative ideas, all designed to be user-friendly, though it is my experience that people react in various ways to such novelties; some actually resent too much machine cleverness. The first thing we meet is the ‘open sesame’ doors of smoked glass which glide open automatically and switch on the inner lights as soon as you advance your hand within 10cm - and glide closed again after 15 seconds, dimming the lights to one-third during play, or switching them off in standby.
The doors give access to a smart central strip of anodised aluminium with a CD deck at the top and a cassette deck at the bottom. Between these we find a long thin display panel and an initially formidable keypad of no fewer than forty thin push-buttons arranged in five horizontal rows of eight. However these are helpfully laid out for easy operation, and the instruction book is very thorough. The ten most common controls (’Primary Functions’) are grouped in the centre and provide source selection (CD, Aux, Tape, Radio), CD tray open/ close, Radio Preset station in two groups—A or B, Volume up/down, Volume Mute and System on/standby.
The display gives immediate confirmation of the system status and pressing the various source buttons a second or third time provides further levels of display information. For example, pressing Radio will switch on the tuner at the last station used and display the RDS station name (in regions where the Radio Data Service is in operation and provided the RDS kit has been fitted—an optional extra), Radio block A or B and stereo/mono. Pressing Radio again displays the preset station number and, for a third time, shows the station frequency. Similarly, pressing CD will start the loaded disc from Track I and display the current track number only. Pressing it a second and third time changes the display respectively to track elapsed time and total time remaining. In the tape mode the displays are simply “FP” and the track number or the 4-digit counter reading. Pressing the Volume up/down buttons produces a display of the current setting in dB and then scales up or down in 2dB steps between 0dB and a very loud 90dB.
The 15 buttons grouped on the left comprise the 0-9 numerical keys, forward/reverse Track or Station skip, set and reset (of various status modes) and “Sound”. This last button toggles between volume, balance, bass, treble and loudness, each suitably displayed and set as required using the up/down buttons. The 15 so-called Secondary Functions controls are grouped on the right. They include Play, Stop (doubling as Pause), Dolby B on/off, tape auto-reverse on/off, manual tuning up/ down, FM/AM, Store, Clear, Turn (e.g. to switch to mono or cassette Sides 1/2), Record, Stop and Return (to rewind the tape to the start of the latest recording, i.e. the spot where you last pressed Record). In the base there is a 35mm mini socket for headphones.
Remote control is available at three levels of sophistication depending on the Beolink unit chosen. The Beolink 1000 handset, included in the basic price, broadly duplicates all the functions listed above and can also be used to control video sources linked through a multi-room Local Control System. The Beolink 5000 and 7000, available at an extra charge, extend operational facilities. Other features such as the synchronised start/stop of tape with other sources, are too numerous to describe fully here so sample details will have to suffice. The phase-lock loop toner has two blocks of 20 presets for either AM or FM stations in any order. The first 15 in each block can be given eight-character personal names using the built-in RDS kit (if fitted). FM tuning is in 50kHz steps and there are steep active multiplex filters to suppress the 19kHz pilot tone for best operation of the Dolby B noise reduction when recording offair. A twin telescopic aerial is supplied which may give adequate reception in favoured areas, either clipped on the back of the unit or wall-mounted. This should be replaced by a proper loft or outside aerial for best results in most areas.
The CD disc tray is vertical (well nearly: the central unit and the loudspeakers are tilted back by 13 degrees) with the disc visible while playing. The disc tray accepts either full-size or 7,5cm CDs and gives secure clamping action helped by a magnet in the chassis. Since the loudspeakers will normally be in close proximity, the CD mechanism is attached to a heavy iron plate, suspended on five steel springs with special damping and the resonance set at an optimum 1215Hz. D/A conversion is dual 16-bit with four-times oversampling. Track sequence programming is provided but each track will play once only and in chronological, i.e. numerical, order. There is no repeat mode.
The cassette deck is also vertical and has auto tape type selection, for normal, chrome and metal formulations. It is auto-reverse for continuous two times 45 minutes recording and playback, and the record level is also set automatically (reducing in 2dB steps to accommodate higher peak signal levels). An auto track search system looks for pauses (a signal below -25dB) of at least three seconds duration and provides sequence programining as on CD, covering Sides 1 and 2 as a whole. Note, however, that pressing Track 3, for example, with a newly loaded tape will cause the machine to rewind to the beginning then fast forward until it finds the third track start. After a tape has been played through, the number of tracks is memorised and direct access is possible. HX-Pro was a B&O development for Dolby Labs and is naturally included along with Dolby B.
A seven-pin Audio Aux Link socket, rated at 1-Volt input, can be used to extend the system to include a B&O turntable with built-in RIAA pre-amplifier, a second B&O audio recorder, or a Beovision video master. In fact any make of unit can be connected, using a standard five-pin DIN plug, but of course the two-way B&O Beolink facilities will then be missing.
Advanced technology has contributed a great deal to this new system, and no more so than in the incredibly slim-line active loudspeakers. The actual enclosure has an internal volume of only 2.8 litres. Frontal dimensions are 260mm wide by 360mm high and the depth starts at only 28mm, increasing to 160mm at the base where the built-in power amplifiers and their cooling vanes are located. The seeming impossibility of producing adequate bass from such a tiny enclosure has been tackled in two ways. First, the 115mm diameter bass drive unit has been specially developed, with a heavier and stiffer diaphragm than usual and with a coil/ magnet system of the long-throw type able to handle large amplitudes without running into non-linear distortion. Second, the built-in amplifiers have been designed not only to make good the low sensitivity implied by that massive, but small diameter, diaphragm and tiny enclosed volume; they also have a response tailored to match the driver properties and boost the bass as necessary. There are separate 70W amplifiers for the woofer and the 25mm tweeter, with active IC-based crossovers prior to the output stages. The filter slopes are a steep 24dB/octave on either side of the 2,500Hz crossover frequency and there is a 30dB/octave roll-off below the bass resonance, which is in effect equalised to +11dB. The result is an effectively flat response from 80-20,000Hz and a maximum output level rated at 103dB SPL at 1-metre in room conditions. A protection circuit is activated to cut the bass in case of malfunction. The treble amplifier has ‘dynamic adaptation’ to check and control strong signals. The amplifiers are switched off when the system is in standby mode.
The enclosure is bass reflex loaded, the spiral shaped port emerging near the top of the back moulding. The enclosure shape practically eliminates parallel surfaces, avoiding standing waves, and a metal plate reinforces the front baffle and adds to the considerable non-resonant mass.
The two drive units are offset towards the outer edge and the left/right speakers are mirrored. A Lycra grille cloth is stretched over a thin plastics frame and is held in place with a simple clip fixing. Six different cloth colours are available, to match different room decors. Any colour can be chosen within the basic price and further grilles can be added for about £10 per pair extra.
In the simplest stand-alone arrangement, the loudspeakers are bolted on either side of the central unit at each end of a substantial bracket which conceals the interconnecting cables. The bracket has carrying handles so that the whole assembly (weighing about 20kg) can be moved around. There is a separate mounting plate which allows the system to be wall-hung on two or more screws.
This sets the loudspeakers only about 70cm apart and naturally limits the stereo spread. This accords with B&O’s idea that the 2500 is an “alternative music system”, typically placed within reach of the listener. However, some users will prefer, at some loss of mobility and convenience, to unbolt one or both loudspeakers to provide the more conventional 2-3 metres spacing. As I have said, both the loudspeakers and the central unit are tilted back at 13 degrees, and ideally a position below eye level will be chosen to put the listener’s ears on axis.
How it performed
The B&O design and engineering team have reason to be proud of the Beosystem 2500. Its simple yet stylish appearance and remarkable compactness give few hints of the sonic pleasures in store. After a short learning curve with the magic doors, the control panel and the Beolink remote control, I came to appreciate the pleasing qualities of the radio, CD and cassette performance. The actual music-centre is perhaps only a slight advance on previous integrated systems from this design-conscious manufacturer, with further miniaturisation made possible through the use of new surface-mount component techniques and the removal of the power amplifiers, transformers and other bulky components to the loudspeakers.
No, the single most spectacular feature is the new Beolab 2500 loudspeaker. Thanks no doubt to scrupulous tailoring of the amplifier response to match the known behaviour of the two drive units, the whole middle and treble registers have been given an incredibly ‘integrated’ smoothness. Running an in-room response curve showed a ±3dB consistency all the way from about 90Hz to 20kHz and beyond. In addition, the robust slimline enclosure revealed no trace of cabinet resonance and the dispersion was wide enough to produce an airy spread of sound, though sometimes at the expense of bass definition. Presence and attack were fine, with voices in particular sounding true to life. It was also possible to increase the volume to well above normal levels and enjoy distortion-free results.
Keeping the loudspeakers bolted alongside the centre unit inevitably restricted the stereo width but the imaginary sound-stage did give a feeling of extending beyond, and even above, the physical dimensions. I made the system nicely mobile by standing it on a wheeled table (actually the stand from a long-deceased TV receiver) and this allowed me to position it a couple of metres from my desk or armchair and produce a near-optimum stereo arc. Alternatively I could place it across a room corner, which paid dividends in terms of simulated spread, reinforcement of the steeply rolled-off extreme bass and amelioration of a certain congestion otherwise heard in ‘busy’ music. In a word this is a fun system rather than something for the dyed-in-the-wool audiophile.
Technical tests on the individual sections showed that they met their respectable specifications. CD frequency response was ruler-flat, with a wide dynamic range and good low-level linearity. Resistance to vibration or feedback was remarkably good. The cassette deck response was within 15dB of the IEC standard overall when replaying calibration tapes. The record/replay response, particularly on chrome tape, was good enough to make input and output signals barely distinguishable except for minimal wow and the very faint tape hiss.
Whether this innovative, compact, and relatively expensive, system is right for you will depend less on technicalities than your attitude to styling and your listening room topography. However, if the whole concept seems to fit, you should be happy in the knowledge that the actual musical performance is of a high order. I have enjoyed seeing and hearing the Beosystem 2500 around the place and, now that it is on its way back to Gloucester, I know I shall miss it as an attractive back-up for my much larger main system.
Taken from ‘Gramophone’ magazine - April 1991 (page 168)
Link: See also Design Prototypes
BeoSystem 2500 types: