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BeoMaster 7000

Bang & Olufsen BeoMaster 7000

Beomaster 7000 was a receiver of high specifications and contained the system infra-red transceiver for communication with Beolink 7000 and the necessary computer to process and relay the commands to the other sources. Beomaster 7000 was the audio master and as such defined the system. Besides being a computer with considerable processing power, Beomaster 7000 also contained an FM/AM radio, the switch circuitry and the control- and power-amplifier.

Features:
Radio:
FM/AM frequency synthesis tuner, 24 presets. RDS decoder with access to FM transmitter name and operator. Naming of individual stations, both FM and AM, up to ten characters per station.

Amplifier Control section:
2 x 110 Watts long-term maximum output power. Automatic Power Handling Control, speaker and amplifier protection. Power Link connection for BeoLab active loudspeakers. Speaker Link connection for other loudspeakers (two pairs).

Connection for external power amplifier. Beolink® AV connection and complete AV operation facilities. Connection for Local Control System.

Audio Master:
Microcomputer, ROM capacity 64 KB, RAM capacity 1 KB, for the control of e.g. adjustments, source switching (audio and video), Automatic Power Handling Control, tuning, timer programming etc. Timer programming, 10 timer blocks. Battery backup for timer and clock. Dynamic display readout on Beolink 7000 of frequency, RDS and naming data, all tuning data, preset, FM/AM, sound adjustments.

Beomaster 7000 had a built-in RDS decoder which gave access to the basic 8 character RDS readout, the “PS” or “Programme Service Name”, i.e. an abbreviated readout of the transmitter name, the programme number and perhaps the name of the operator. The RDS data was displayed directly on Beolink 7000, when you selected a station that broadcast RDS information. This applied both when you were tuning or when you selected the preset that you had stored the programme on. Beolink 7000 displayed the RDS data also in situations when you were in a room equipped with Local Control System. Beolink 7000 was the only remote control capable of displaying RDS data.

The channel-naming facility allowed you to give every single radio station a name of your choice, with up to 10 characters, directly on the Beolink 7000. Naming could be carried out on all preset stations. Your favourite name had priority over a RDS name (if available) and was displayed when you selected the channel number.

The RDS and naming facility gave an added convenience with radio reception. The convenience level was paralleled with the reception quality of the FM tuner.

An FM tuner faces conflicting demands with regard to signal reception. It must have a high sensitivity for receiving weak stations (high selectivity), but it must also be able to suppress interference from powerful neighbouring stations. Beomaster 7000 was one of the few receivers that paid attention to these conflicting demands.

Components in high quality (e.g. dual-gate MOSFET transistors) and an optimised electronic design were used. The Intermediate Frequency (IF) stage had a bandwidth of approximately 200 kHz around the 10,7 MHz centre frequency (the IF filter contained three stable ceramic filters). Generally, if the IF bandwidth is broad, the selectivity falls, as does the intermodulation distortion. Conversely, if the bandwidth is narrow, the distortion and selectivity rise. This relationship must be compared with the reception conditions. If stations are close by (and powerful), the ideal is a narrow bandwidth, while distant (weak) stations require a wider band, in order to keep down the intermodulation distortion. In Beomaster 7000 the signal strength was measured for both the stations you received (within the filter range) and for stations that you didn’t want to receive, outside the filter range. This allowed Bang & Olufsen to suppress powerful stations on neighbouring frequencies and counteract intermodulation distortion, giving a high signal-to-noise characteristic for both weak and strong stations.

The stereo decoder gave an optimal stereo channel separation as long as the signal-to-noise ratio in the received signal was above 50 dB. When weaker signals were received, Beomaster 7000 automatically switched to mono. You could also select mono manually.

Tuning
The tuner was of the frequency-synthesis type, based on digital technology and controlled by the microcomputer. Tuning on FM was in steps of 50 kHz, in order to adhere to the cable network frequency allocation of 50 kHz. Tuning was carried out from Beolink 7000, either as a search tune up or down in the frequency range, or by direct frequency selection. There was automatic or manual fine-tune, with a precision better than 1 kHz.

AM Tuner
The (then) newly-developed AM tuner had a high reception sensitivity and was very stable and reliable. It was optimised for the Bang & Olufsen loop antenna, type no. 8720038. Automatic tuning was in steps of 9 kHz (USA: 10 kHz). The fine-tune operated in steps of 0.25 kHz.

Presets
24 presets were available. You could store any FM or AM station in any order and information such as fine tune, FM stereo/mono and AM manual tune was stored on the preset.

The Power Amplifier
The power amplifier in Beomaster 7000 was rated at 2 x 110 watts long term max. output, and it featured Automatic Power Handling Control as a protection for both the loudspeakers and the amplifier in case of overload or shorting. The circuit monitored the critical stage in the output amplifier and if prescribed limits were exceeded, the microcomputer lowered the volume to below the critical level.

The temperatures of the cooling surfaces were also measured and if the temperature got too high, the volume was also cut down. If the limits were exceeded again, the procedure was repeated. If the cause of the overload was eliminated, the volume could be turned up above the previous critical level. You would only under very special circumstances experience the Automatic Power Handling Control’s circuit overruling your volume setting, but when it did, it could save the system from serious damage. The circuit might have been activated, for example, if you connected several pairs of normal loudspeakers and played very powerful music extremely loudly. Another example could be if the loudspeaker outputs were short-circuited, in which case the Beomaster was simply switched to stand-by to protect the amplifier in an effective way. Similarly, if a defect occurred in the amplifier, the circuit protected the loudspeaker against direct current, which would otherwise destroy them.

If you connected BeoLab Penta or other active BeoLab speakers via the Power Link sockets, there was an independent protection circuit in the loudspeakers to protect them in a similar way.

Active cooling
Beomaster 7000 was very compact and in order to liberate heat from the power amplifier efficiently, a low-noise fan was placed at the bottom of the cabinet. If the cooling ribs of the output transistors reach a temperature of more than 50 degrees, the fan started up at low speed, rising to a maximum speed when the temperature was around 95 degrees. The amount of heat generated by the amplifier depended on how loud you played and for how long a period the volume was turned up. Only by playing very loudly for a prolonged time would the temperature rise and the fan start up, or the Automatic Power Handling Control interfere. Note also that if the recommended BeoLab Penta loudspeakers were connected, the power amplifier in Beomaster 70000 became inactive (or perhaps used to drive a Local Control System).

PowerLink Connection
The PowerLink connection in the receiver was used to connect BeoLab active speakers. The signal is a volume-adjusted line level signal and both left and right signals are carried in one cable, with data signals for a BeoLab status display. This means that it is no longer the socket on the Beomaster that decides whether it is the left or right channel. Instead a switch on the BeoLab loudspeaker has to be set to the correct position. PowerLink is very flexible with regard to connections. A pair of loudspeakers can be connected the usual way, with one cable to each loudspeaker, a BUS system can be applied where the signal is looped through one of the loudspeakers and then on to the next, or both methods may be combined if more than one pair of speakers needs to be connected. No matter which method is used, the correct setting of the L – R switch on the loudspeaker is essential. Up to 10 pairs and 100 metres of Power Link cable is recommended.

Socket Panel
The socket panel on the back of Beomaster 7000 was placed in a cut-out to prevent the connectors from protruding too far. As a consequence, the effective depth of Beosystem 7000 was virtually the same as the actual depth of the components. Apart from the CD, Tape 1, Tape 2, Phono and PowerLink sockets there were also connections for TV (or AUX), 2 pairs of Speaker Link for normal loudspeakers and Local Control System, FM/AM antenna sockets and a Line in/out socket for an external unit, e.g. an equaliser.

Note that the RIAA phono-preamplifier was placed in the Beogram 7000 and if a Beogram without RIAA was to be connected, a RIAA kit must be mounted in Beomaster 7000 by means of a minor service operation.

The battery backup in Beomaster 7000 retained all information in case of a power cut, where a quartz crystal was used as a reference for the clock.

Beomaster 7000 could, ideally, be used as part of Beosystem 7000.

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BeoGram CD 3500

Bang & Olufsen BeoGram CD 3500

The sound reproduction achieved by Bang & Olufsen’s CD 3500 CD player was truly outstanding. It played both 12cm and 8cm compact discs and had an ingenious ‘step’ function which allowed you to go straight to a chose track selected from anywhere on the disc. The CD player was one of the most technologically-advanced pieces of hi-fi on the market at the time and yet was one of the easiest to operate. The explicit display always indicated what the CD player was doing all the time – for example, which track was being played, and how many tracks there were on the played compact disc.

Beogram CD 3500 could be used as part of the Beosystem 3500 hi-fi system.

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BeoLab 5000 (1988)

Bang & Olufsen BeoLab 5000 1988

Bang & Olufsen’s BeoLab and Beovox 5000 / 3000 speakers had both the voice and the looks for a leading, acoustic role. And because of their looks, they were known as Bang & Olufsen’s range of panel loudspeakers. Panel loudspeakers were one of the most exciting and interesting examples of how Bang & Olufsen united advanced technology and stunning design to achieve totally new effects.

They may not have looked like high-specification loudspeakers – more like works of art – but their sound immediately gave them away. Even at full volume, they kept the total sound picture in perfect balance.

Design as a work of art
The elegant, flat panel loudspeakers were created to hang on the wall. And with their calm surfaces of blue or grey fabric coupled with polished steel, they could be taken for works of art. But the design was only partly for visual effect. The form of the panel speakers was founded on an advanced, acoustic principle that uses the wall as an active part of the sound reproduction process – without causing the wall itself to vibrate.

Optional display and amplifier
The panel loudspeakers were available in two sizes – each with or without amplifier and a display showing which source was playing and at what volume. Also it told you which track number on a CD or tape you were listening to. With display and amplifier the loudspeakers were called BeoLab. Without, they were called Beovox. The option depended upon which Bang & Olufsen sound system was connected. BeoLab speakers were designed to match Beosystem 6500, 4500, 3500 and Beocenter 9500 and 8500.

Why build amplifiers into the loudspeakers instead of keeping them separate?

Because you can reduce the size of the cabinet volume to one-third of the size of a conventional loudspeaker with the same sound capacity. The principle is called Active Loudspeakers, and what you get is a compact loudspeaker that can play at high volume without distortion or damage to its drive units. Furthermore, when amplifier, treble and bass units are paired for the same task, they can be tailored to compensate for each other’s shortcomings. What you hear is music that sounds exactly like the instrument it originally came from.

Mounting Options
Wall mounting brackets were supplied with this model. No other mounting solution wall offered.

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BeoCord 3500

Bang & Olufsen BeoCord 3500

Beocord 3500 was part of Beosystem 3500, a budget-priced system for those who wanted to get onto the Bang & Olufsen bandwagon but could not afford, or did not want to have, the extra features that say, Beosystem 4500 had to offer.

It included specifications such as Dolby B Noise Reduction and a Sendust head for longer life of the recording/playback head, otherwise the features were identical to the Beocord 4500. Its only difference was the grey finish instead of its more expensive brother’s polished surfaces.

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BeoVox CX100

Bang & Olufsen BeoVox CX100

Living proof that big sound need not take up more space than a couple of ring binders, Beovox CX50 snuggled in anywhere, even as extras in a Beolink® system.

Beovox CX50 and Beovox CX100 loudspeakers were the smallest loudspeakers from Bang & Olufsen up to the time that the manufacture of passive speakers ceased in 2002. They were mostly used to place within a passive Beolink® system (MCL), although they could also be used as main speakers. Thanks to different colour combinations they blended well into most people’s décor.

Beovox CX100 finally ceased production in September 2003 – the last of a long and successful line of passive speakers.

Description:
Passive loudspeaker, aluminium cabinet, available in black, white and brushed aluminium.

Replacement drive units: Top drive unit for CX50/CX100 Part number: 411743

Mounting Options
BeoVox CX50/CX100 replaced C40 and was designed to be optionally mounted with the wall brackets supplied in the box.

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BeoVox CX50

Bang & Olufsen BeoVox CX50

Living proof that big sound need not take up more space than a couple of ring binders, Beovox CX50 snuggled in anywhere, even as extras in a Beolink® system.

Beovox CX50 and Beovox CX100 loudspeakers were the smallest loudspeakers from Bang & Olufsen up to the time that the manufacture of passive speakers ceased in 2002. They were mostly used to place within a passive Beolink® system (MCL), although they could also be used as main speakers. Thanks to different colour combinations they blended well into most people’s décor.

Beovox CX100 finally ceased production in September 2003 – the last of a long and successful line of passive speakers.

Description:
Passive loudspeaker, aluminium cabinet, available in black, white and brushed aluminium.

Replacement drive units: Top drive unit for CX50/CX100 Part number: 411743

Mounting Options
BeoVox CX50/CX100 replaced C40 and was designed to be optionally mounted with the wall brackets supplied in the box.

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BeoVox Cona

Bang & Olufsen BeoVox Cona

By using smaller loudspeakers in the Bang & Olufsen range – like the BeoVox CX50 or BeoVox C75 passive speakers, all it took to fill out the sound even more was the BeoVox Cona, a passive sub-woofer.

Beovox Cona functioned almost like a prompter who ensured that the sound didn’t forget its ‘lines’. It worked on the principle that the human ear cannot detect in which direction deep tones are coming from. Beovox Cona, like the newer BeoLab 2, could therefore be placed anywhere in a room with the rest of the music system to give it a deeper, much richer sound.

Review by BeoWorld Member – Evan Bunner

The BeoVox Cona Having waited very patiently for a Cona to come my way, I finally stumbled across not one, but two BeoVox Conas on the internet. I quickly arranged a demonstration the next day. It didn’t take very long to impress me. I loaded the pair into my car with a great sense of satisfaction. However, I had to wait for some din plugs I had ordered off the internet before I could start using them, so my excitement was slightly delayed.

My excitement soon resumed once I received my din connectors. I hastily fashioned them together with some surplus speaker wire of mine and proceeded to connect one of the Conas, as originally directed, to my BeoMaster 4500. Being a passive speaker, it is very handy when you have your Power link ports all filled up with your favorite BeoLab speakers.

Being able to channel both left and right signals to one diver through the Cona’s dual voice coil feature allows the Cona to produce BeoLab level sound at a BeoVox level price. However, I find that combining two signals in a single driver does make the sound much choppier than say if you were to connect two Conas, one signal assigned to each. Additionally, this fight over the driver can create some enclosure rattle, something that can become annoying in heavier listening. I find that a stereo configuration generates much more natural sound.

Since it is a passive speaker, the driver is much smaller than what you would find in an average standalone subwoofer, mostly due to the fact that it has to be able to perform on less power, keeping the Cona from being power hungry. This directly affects the range of the speaker. Being slightly smaller than most standalone subwoofers, the Cona is slightly heightened in the frequency range, making it more of a musical speaker while slightly lacking in movie listening. The heightened frequency range is not very noticeable at higher volumes due to the great amount of bass the Cona can deliver higher up on the volume scale.

In usual Bang & Olufsen style, things are much more aesthetically pleasing and interesting than the bland norm that comes with most other loudspeakers. The BeoVox Cona is no exception.

Visually, the BeoVox Cona generates several comments. First off, one notices the size, very large for a single driver, especially that of 8 inches. This quality quickly earned the title “ottoman” by my girlfriend. So far I have not found a corner the Cona could not squeeze into, so it is a very practical size. They are very subtle but can also retain a good focal point in a modernly appointed room. The roundness of the Cona is a nice departure from the cubic trend of standalone subwoofers we are all used to seeing. I like to maintain the idea that the form of the Cona also serves a function. Coming from the same time period that gave us the Penta and Red Line speakers, I believe that the Cona followed a common trend set by the Penta and Red Line speakers in utilizing a unique cabinet shape to reduce internal acoustic reflections and standing waves by removing parallel surfaces from the construction.

For the first attempt at an individual subwoofer, Bang & Olufsen hit a home run. The sound is very rich and full. The bass is very tight and responsive, even on as little as 55 watts. The bass is light in quantity down low on the volume scale, but can still annoy the neighbors when you crank up the volume. This is definitely a piece for collector interested in past Bang & Olufsen products.

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BeoCom 2000

Bang & Olufsen BeoCom 2000

Beocom 2000, the classic telephone from Bang & Olufsen… what else is there to say?

Beocom 2000 was unlike anything which had been introduced by Bang & Olufsen before.

All the parts of the phone were made by the company itself and not imported from other manufacturers. A well-equipped telephone with extraordinary sound quality, a tradition carried on with all of the Beocom range of telephones.

The design is truly timeless. The display gave information on which number your were calling and the time connected. All standard functions were of course, also available, like volume control and numeric memories, and for the more advanced user there was a special headset available!

This phone was also available in a more simple version, Beocom 600, which didn’t have the display but had the same sound quality.

The memory bank of the Beocom 2000 enabled you to store your personal top twenty, and at the touch of just a few buttons you were connected. With display, bass reflex speaker in handset, 20 numbers of memory, quick call key for an often-use or ’emergency’ number, redial of last 3 numbers called, pause function, adjustable volume control, microphone mute (for secrecy), built-in speaker for listening, adjustable tone ringer with 8 settings plus off. There was even a hidden note pad which could be used by raising the lid on the right-hand side of the unit!

Up to 1993 Beocom 2000 was produced with different coloured keys. However, from this time a more mellow design was offered with all the keys complementing each other. On its bright display with large characters the Beocom 2000 could offer you the last three numbers for redialling