Cube/Sphere, Shelf speaker   as in Hobby HiFi 4/2010

Technical data
- impedance: 6 Ohm
- sensivity (2,83V/1m): 83,5 dB
- size (HxWxD): 106 x 106 x 206 mm
- frequency range (-8dB): 97 - 38000 Hz
- crossover frequency(s): Hz
- speaker type: closed box

As one of their Clever Concepts the magazine Hobby HiFi presents the Omnes Audio BB3.AL full range driver in a cuboid enclosure (Cube) or in a spherical enclosure (Sphere).

The advantage of the spherical enclosure:
- less reflection in the absence of parallel walls
- less diffraction at edges, since there are fewer edges.

As a result, the magazine Hobby HiFi regards the sphere as the better solution. In view of the lab results in Hobby HiFi this seems to be difficult to understand. The Sphere’s 14dB total non-linearity of the frequency response is 2dB higher than that of the Cube’s.

How is that? The answer is obvious: due to the different distance of the edge to the radiation centre the Cube’s edges have a different effect depending on the location. Considering the Sphere, the flattened baffle’s edges have the same effect if the sphere radiates on axis.

The midrange of the Sphere, however, shows a more even frequency response.

An interesting compromise would be a cube with edges that are chamfered with 45 degree angles instead of 90 degrees.

The speaker comprises a small crossover to compensate for baffle steps. The crossover consists of a wave trap in series to the full range driver and a linearising component.

An excerpt from the Hobby HiFi review

"Even though the dynamics of the petite satellites are somehow limited, the imaging is magnificent. The “O-Zone Percussion Group“ (e.g. on the Manger Test CD) requires high dynamic abilities in all frequency ranges, the Sphere complies with the requirements. The Spheres reproduce a punchy and solid sound. The stage’s depth ranges from close by to faraway. The music is detached from the speakers with rarely experienced perfection. Every instrument sounds real and within your reach. When the Cube replaces the Sphere the sound remains powerful and tight. The splendid effortlessness, however, is not quite the same anymore; everything seems to be less natural. That’s a quite convincing advantage spherical loudspeaker cabinets, showing benefits that could be imagined by looking at the lab results and were clearly confirmed by listening. "
 

   

Our kit consists of

  • Omnes Audio full range BB3 AL
  • 1/2 Polyester damping material, 125 g for 20L volume
  • Binding Post PK31 (red and black)
  • 1m Speaker cable 2x1.5 mm2, transparent
  • Pan screws 3.5x17 black, 4 pieces
  • Plan for DIY kit

the crossover components (right),
to be mounted on a small wooden board.

  • electrolytic capacitor, unetched, 6.8 μF / 70 Vdc
  • electrolytic capacitor, unetched, 15uF / 70 Vdc
  • 1.0 mm Air core coil, 0.27 mH/0.23 Ohm
  • 1.0 mm Air core coil, 0.33 mH/0.26 Ohm
  • MOX4 resistor 5.6 Ohm/4 Watt (green-blue-gold)
  • MOX4 resistor 6.8 Ohm/4 Watt (blue-grey-gold)
  • MOX4 resistor 8.2 Ohm/4 Watt (grey-red-gold)

*) Parts are only used for DIY-kit Cube or Sphere (not for both kits).

Kit with all parts to build one of both kits without cabinet - not available

Kit for Sphere without cabinet, price per speaker - not available

Kit for Cube without cabinet, price per speaker - not available
 

 

If you prefer to mount the crossover components on a 140 x 102 mm universal PCB instead on wood:
Universal PCB RA140, order no.. str-RA140, price per unit: EUR 4,20 excl. VAT: € 3.53 / $ 3.95
We recommend one boards per kit (two boards for a speaker pair)
 

  

Kit Sphere with high-end crossover

In our high-end version only Tritec/Hepta coils are used in the signal path to the full range and polypropylen (MKP) capacitors are used.

  • MKP capacitor 6.8 μF / 400V
  • MKP capacitor 15 μF / 400V
  • Tritec/Hepta coil 0.27 mH/7x0.6 mm, 0.13 Ohm
  • MOX4 resistor 5.6 Ohm/4 Watt (green-blue-gold)
  • MOX4 resistor 8.2 Ohm/4 Watt (grey-red-gold)

Kit shere with high-end crossover without cabinet, price per speaker - not available (_)

Kit Cube with high-end crossover

In our high-end version only Tritec or Hepta coils are used in the signal path to the full range and polypropylen (MKP) capacitors are used.

  • MKP capacitor 6.8 μF / 400V
  • MKP capacitor 15 μF / 400V
  • Tritec/Hepta coil 0.33 mH/7x0.6 mm, 0.14 Ohm
  • MOX4 resistor 6.8 Ohm/4 Watt (blue-grey-gold)
  • MOX4 resistor 8.2 Ohm/4 Watt (grey-red-gold)

Kit cube with high-end crossover without cabinet, price per speaker - not available
 

 

If you prefer to mount the crossover components on a 140 x 102 mm universal PCB instead on wood:
Universal PCB RA140, order no.. str-RA140, price per unit: EUR 4,20 excl. VAT: € 3.53 / $ 3.95
We recommend one boards per kit (two boards for a speaker pair)
 


Home   Hobby HiFi Overview