Cobra-Horn RBT   Floorstanding as in Hobby HiFi 5/2015

Technical data
  • impedance: 8 Ohm
  • sensivity (2,83V/1m): 93 dB
  • size (HxWxD): 1078 x 338 x 500 mm
  • frequency range (-8dB): 50 - 30000 Hz
  • crossover frequency(s): 5000 Hz
  • speaker type: Horn

Cobra-Horn RBT is huge speaker with Monacor fullrange loudspeaker SP-200X and magnetostat Monacor RBT-95SR. It has been developed by Bernd Timmermanns.

The crossover consists of a 2nd order low-pass filter (12 dB per octave slope) for the fullrange speaker and a 2rd order high-pass filter for the magnetostat

The frequency response of this loudspeaker is suitably flat.

Our kit consists of

  • magnetostat Monacor RBT-95SR
  • Monacor SP-200 X full range driver
  • 0,5x PE sealing tape, 5x2 mm, 7.5 m
  • 2,5x Damping Sonofil 100 x 35 cm for 20 litres
  • Binding Post PK31, gold plated (one pair, red and black)
  • 2m Speaker cable 2x2.5 mm2, transparent
  • Pan screws 4x20 black, cross recess, 8 pieces
  • Plan for DIY kit

the crossover components (right),
to be mounted on a small wooden board.
  • Audaphon MKP CAP Superior 2.7 uF / 400 Vdc
  • Audaphon MKT CAP 1.5 uF / 160 Vdc
  • 1.0 mm air core coil, 0.47 mH/0.32 Ohm
  • 0.7 mm air core coil, 0.15 mH/0.28 Ohm
  • MOX5-resistor 68 Ohm/5 Watt (blue-grey-black)
  • Metal-oxide resistor, 5W 0.68 Ohm 5% (blue-grey-silver)
  • Metal-oxide resistor, 5W 4.7 Ohm (yellow-violet-gold)

Kit without cabinet, price per speaker   EUR 154,00 excl. VAT: € 129.41 / $ 146.24

Kit with high-end crossover

The high-end kit comes with Mundorf MCAP capacitors. The inductances are baked varnished coils for minimizing microphonic effects. - The current flow through the coil creates a magnetic field which sets the reel of wire in motion. This motion induces a voltage in the coil which adds itself to the signal. The stiffer the reel of wire is, the less the signal will be altered.

Kit with high-end-crossover without cabinet, price per speaker   EUR 174,00 excl. VAT: € 146.22 / $ 165.23

Impedance correction

If you want to use a valve amplifier with this speaker an impedance correction should be employed. In this case the component quality is less important; therefore, we offer only one kit (upon request higher quality components are available).


Price per impedance correction for one speaker, to be mounted on a small wooden board.     EUR 8,00 excl. VAT: € 6.72 / $ 7.60

universal PCB

If you prefer to mount the crossover components on a 140 x 102 mm universal PCB instead on wood:
Universal PCB RA140, order no.. I-2765, price per unit:   EUR 3,70 excl. VAT: € 3.11 / $ 3.51
We recommend one board per kit (two boards for a speaker pair)


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