BR 25

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BR25 is the name for a loudspeaker box that has been produced in the GDR since 1984 . Around 650,000 of these had been produced by 1990. The box was designed by VEB Musikelectronic Geithain .

history

At the end of 1984 VEB Musikelectronic Geithain presented the two-way bass reflex loudspeaker type BR 25 at the Leipzig autumn fair. Characteristic is not only the tonally very clean and level stable music reproduction, but also the solid workmanship with conspicuous rounded corners of the sound box. In addition to the classic colors black , dark brown and dark gray , a version in silver , which was unusual at the time, was also offered.

Initially, the BR 25 was manufactured on the company's own premises in Nikolaistraße, but due to the high demand, production was transferred to the significantly larger company Statron Fürstenwalde in 1985 . Half of the loudspeakers produced there were exported to Germany . There they were sold in large quantities at Conrad Electronic and soon gained a good reputation in the West German music scene. The sales price per box was 69.50 DM at the time. Despite this rather small amount, the sale of the GDR brought in urgently needed foreign currency.

Modifications of the BR 25 were the BR 25E (presented at the Leipzig Spring Fair 1985) as well as the BR 26 (1987) and the BR 2725, which were only characterized by optical changes (such as the use of a loudspeaker cover or changes to the acoustic elements on the baffle ). The acoustic properties of these "sister models" do not differ from the original form of the BR 25. Die-hard fans and listeners attest that the BR 25E and the BR 26 nevertheless have slightly different properties in terms of bundling and other acoustic details.

Technical specifications

  • Nominal load capacity: 25 W
  • Maximum load capacity: 50 W
  • Nominal impedance: 4 ohms
  • Transmission range: 45 - 22000 Hz
  • Crossover frequency: 2.0 kHz
  • Sound pressure level: 86 dB
  • Net volume: 8.5 l
  • Dimensions (W × H × D): 205 × 290 × 255 mm
  • Mass: 6.0 kg
  • Price per box: 250 M

Trivia

  • A car light bulb (brake light, 12 V, 21 W) is used as a PTC thermistor on the loudspeaker crossover in this box to protect the tweeter (fabric dome) from overload.
  • The surrounds of the bass-midrange speaker are made of thermomechanically pressed foam, the repair of the surrounds is still offered today by the developer of the box.
  • The coil of the bass-midrange speaker is wound on an aluminum carrier, which considerably increased the electrical load capacity of the box compared to the other products on the GDR market, as better heat dissipation was guaranteed.
  • The loudspeakers used in the BR 25 were used in the BR 25E, BR 26, BR 2725 and BR 3750 boxes, similar to a modular system. They were available as an 8-ohm variant (BR 50 woofer), 4-ohm variant with a shortened voice coil (BR 50 mid-range speaker) and the normal 4-ohm variant.
  • The two coils on the crossover are made of aluminum tape because of a lack of material (copper wire). The connection from the aluminum strip to the contact pin, which is soldered to the crossover, is a frequent cause of failure today. Replacement with conventional copper coils with the same electrical values ​​and tolerances is possible without any problems.
  • In the competition for the coveted Q quality mark, the VEB RFT Kombinat Nachrichtenelektronik Leipzig with its product B9271 "Corona" was defeated, despite the planned economy there was an ideal competition between these VEBs.
  • The BR 25 was due to its clean sound reproduction z. B. used in OB vans ( Barkas ) for prior checking. The RL 900 of VEB Musikelectronic Geithain was installed in all radio facilities in the GDR from 1985. Both loudspeakers, both the RL 900 and the BR 25, benefited from the research work carried out by Joachim Kiesler, who is still the managing director of Musikelectronic Geithain GmbH today (as of January 2016).

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