The Oberton driver D3672 that we chose is a compromise since the frequency
range goes beyond 10 kHz. In conjunction with the horn H955, providing a constant
but slow drop, the frequency response could be extended with the support of
the crossover to 15 kHz (-8dB), respectively 12 kHz (-3 dB).
The proven Oberton 15B450 was added as bass driver. In an 80 litre volume
bass reflex cabinet the frequency range starts at 48/60 Hz (-8/-3 dB).
At 1.3 kHz the driver shows a slight anomaly. Otherwise, the total
frequency response is quite flat. At the crossover frequency of around
1.5 kHz the intersection of the sound pressures (red and green curve)
of the individual drivers are roughly 6 dB below the sound pressure
level of the loudspeaker (black curve). This means that the crossover
drives the drivers in phase.
Picture 2: Frequency response of the loudspeaker at an angle of 0 degrees,
15 degrees, 30 degrees, 45 degrees and 60 degrees.
Up to an angle of 30 degrees the physically determined grouping effect
(clearly noticeable at the crossover frequency of the bass driver at
1.3 kHz) is still low enough.
Picture 3: Impedance dependant on frequency. The bass reflex tube's
resonance is quite low.
The crossover components need to be mounted on a wooden panel and attached
to the inside of a wall. The terminal may be mounted anywhere on the
All drivers are to be screwed onto the baffle from the front.
For hi-fi applications we recommend, in addition to the nap foam for
the rear wall, 2 packs of damping fleece.
Do you prefer a more professional cabinet?
Then we recommend to taper the rear of the cabinet. The front wall should,
therefore, be 2 cm wider (i.e.. 480 mm). To ensure the same volume the
cabinet needs to be 130 mm deeper (i.e. 500 mm). The rear wall's width
is then 212 mm.
Price per unit without cabinet and wood: EUR 449,00
In case you prefer to mount the crossover components on a PCB with Cu spots,
we recommend to use 2 PCB's per loudspeaker.
Price of PCB 205 x 140 mm EUR 11,70