BeoLab Penta Active Loudspeakers

BeoLab Loudspeaker

Production: 1987 - 2000

BeoLab Penta - top quality went higher

These tall and elegant speakers were developed according to a totally new acoustic principle. They sounded just as magnificent as they looked. Because there were no parallel surfaces in the pentagonal cabinet, the design reduced the internal standing waves and reflection; it was a simple and beautifully effective way of eliminating distortion. The cabinet provided the ideal conditions for the loudspeakers. It was an acoustically 'dead' construction, with a moulded inner cabinet surrounded by a stainless steel exterior. Whatever the dimensions of your room, and regardless of the furnishings, BeoLab Penta always sounded wonderful. It also needed very little floor space; head room was all that's required!

BeoLab Penta was the top-of-the-line speaker from Bang & Olufsen. It was around from the late 'eighties to the mid-1990s and was upgraded several times. The last version of the active Penta was the Penta 3. In the late 1980's - when the Penta range was introduced - there was also a passive version, Beovox Penta. But since Bang & Olufsen decided in the 1990s just to concentrate on active speakers, these and some other models, such as the Beovox 4500 and most of the RedLine speakers, were discontinued.

Did you know that the display in Penta I and Penta II was orange and and on Penta III it turned green?

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.

BeoLab Penta had nine individual loudspeaker units that were accurately positioned in a vertical line to produce a sound dispersion which was so precise that reflections from the floor and ceiling were eliminated. Consequently, Penta speakers could be placed almost anywhere in a room, irrespective of its size or furnishings. The operating panel at the base of BeoLab Penta allowed for the fine tuning of the bass reproduction at three levels.

The speaker's cross section was a pentagon. The benefit of this design was that it cannot house standing waves which normally are a problem in speakers. The choice of using polished stainless steel was made to help the speaker blend into its surroundings by reflecting them. This gave the speaker the same colour as the surroundings which helped to make the speaker more of a subtle fixture,

Sound with as many facets as a diamond

The location of the speakers within the column was carefully planned to control the sound waves so that they weren't reflected by the floor and ceiling. The resulting sound quality simply beggared description.

BeoLab 150: Controlled overdrive

At the base of BeoLab Penta was the BeoLab 150 amplifier with a power output of 175 watts DIN/IEC. This could give your music a tremendous boost, both to the quality and the actual power output. It was ideal if you love partying but had a relatively small music system. Big power needs careful control - so the amplifier was equipped with Dynamic Soft Clipping system. When there was any overloading, the system softly rounded off the sound; distortion becoming a thing of the past.

Speakers that more than measure up

Top quality music systems need the best speakers available - or you're missing out. BeoLab Penta was the natural partner for Bang & Olufsen's Beosystem 5000 and Beocenter 9000, with their built in CD players. The laser-pure quality of compact disc makes heavy demands on speakers, and both these systems had extremely fine amplifiers. Using BeoLab Penta with these systems and you'd enjoy some of the best sounds in the world. You'd also appreciate handy features such as the light display at the base of the column, which indicated which music source was being used. Of course this was even more useful if you installed Beolink® to give you music all over the house.

BeoLab Penta Active Loudspeakers technical specifications

Beolab Penta 1

Type no; year intro; last sold: 
6601 1986 05-89 
AUS 6605 1986 10-89 
GB 6602 1986 10-89 
J 6604 1986 11-89 
USA 6603 1986 11-89 

RMS power handling capacity 150 watts 
Music power handling capacity 200 watts 
Frequency range +4 -8 dB 40 - 20,000 Hz 
Power at 96 dB SPL 2.5 watts 
Sensitivity 92 dB 

Distortion 250 - 1000 Hz <0.5% 
Distortion >1000 Hz <0.5% 

Cabinet principle: Bass reflex 
4 units 13 cm 
Mid-range 4 units 8 cm 
Tweeter 2.5 
Net cabinet volume: 32 litres 

Power amplifier: 
Bass level switch Linear, +3 dB/40 Hz, +6 dB/40 Hz 
Sensitivity 3 dB, -3 dB, -6 dB 

Power supply 
6601 : 220V 
6602/6605 : 240V 
6603 : 120V 
6604 : 100V 
Power frequency 50-60 Hz 
Power consumption Max 300 W 
Stand-by 2 W 

Dimensions W x H x D 
5-13.5 x 165 cm incl. stand 
Weight 24 kg 

Connections: Line Phono plugs 
Power input 4-pin DIN spring loaded contacts 

Beolab Penta 2

Type no; year intro; last sold: 
6621 1989 05-92 
AUS 6625 1989 09-91 
GB 6622 1989 10-91 
J 6624 1989 01-92 
USA 6623 1989 12-91 

Long-term maximum power IEC 320 watts 
Maximum noise power IEC 150 watts 

8 ohms 

Frequency range +4/-8 dB 
40 - 20,000 Hz 

Power at 96 dB SPL (1m) 
2.5 watts 
Sensitivity 1 W (1m) 92 dB 
Distortion 0.250 - 6 kHz <0.5% 
Cabinet principle: Bass Reflex 
Woofer: 4 units 13 cm 
Mid-range: 4 units 8 cm 
Tweeter: 2.5 cm 

Net cabinet volume:32 litres 

Power amplifier: 
Long-term maximum power IEC 300 watts 
RMS DIN 175 watts 
IHF 150 watts 

Total harmonic distortion IHF <0.015% 
Intermodulation IHF <0.02% 
Dynamic headroom >1.5 dB 

0 dB, + 3 dB, + 6 dB 
INPUT LEVEL switch 0 dB, -3 dB, - 6 dB 
Dynamic Clipping Attenuator Automatic 

Power consumption 
Max. 300 W 
Stand-by 2 W 

Dimensions W x H x D 
22 x 165 x 20.5cm 
Dimensions, stand 35.5 x 4 x 34 cm 
Weight 24 kg 

Connections: Power Link 
Speaker Link 

Beolab Penta 3

Type no; year intro; last sold: 
6631 1991 05-2000 
AUS 6635 1991 05-2000 
GB 6632 1991 05-2000 
J 6634 1991 05-2000 
USA 6633 1991 05-2000 

Dimensions W x H x D/Weight: 22 x 165 x 34cm / 12kg 
Cabinet finish: Stainless steel 

Power consumption 
Typical 24 watts/stand-by < 2.5 watts 
Mains 6630 KOR 120V 
6631 EU 230V 
6632 GB 230V 
6633 USA-CDN 120V 
6634 J 100V 
6635 AUS 240V 

Maximum sound pressure level (stereo, pair) 
103 dB 
Power amplifier modules 1 unit 
Long-term maximum output power per module* 281 watts 
Effective frequency range* 39 - 20,000 Hz 
Cabinet principle Bass Reflex 
Magnetic shielded No 
Woofer 4 x 13 cm 
Midrange 4 x 8 cm 
Tweeter 2.5 cm 
Net volume 32 litres 
Bass equalizer Switch 0 dB, -3 dB, +6 dB 

*According to IEC 268-3 and 268-5 

Connections: Power Link 2 
Phono (line) 1 
Speaker Link 
Most recent S/W 1.1

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