Dipole 08 … An Open Baffle Loudspeaker and its Philosophy Behind

This is a Preliminary Description of a Private Developmental Project concerning

HiFi Loudspeakers Based on Open Baffle

© Oliver Mertineit

oliver.mertineit@ymail.com

The best loudspeaker enclosure is no enclosure at all

Loudspeaker enclosures tend to colorate and distort the sound. Especially in the bass and midrange there are significant discolorations caused by cavity and material resonances, which are present in almost every enclosure, even if constructed and built carefully. With Dipole 08 it was achieved to rebuilt cavity and reflective surfaces to renounce entirely. By carefully adding sound radiated from 6 equally built sources, an extension of reproduction down to the bass range has become possible, without the need for an enclosure, a large size baffle or baffle wings.

The ideal Loudspeaker is said to be made up from a single sound source

As an approach to this ideal notion, dipol 08 represents a virtually coherent sound source made up from a multitude of small and equal transducers. This way the inevitable drawbacks present with large speaker cones are circumvented, which again would cause sound discoloration. 6 selected high quality fullrange transducers are driven in a way, to make up a line source in the living room, which adapts its effective length according to the wavelength radiated. Even the mid and upper bass range, which contributes to spatial imaging, is radiated from the line array. Below 70Hz the system is crossed over to a dedicated subwoofer, which works as a dipole radiator too, thereby being able to reproduce organ pedal tones e.g. lifelike and without booming or the feeling to be set under pressure while listening.

The best way of sound radiation is controlled angular dispersion over the entire listening range of frequencies

Only a loudspeaker which is able to radiate the whole range of relevant frequencies with even angular dispersion, will sound equally well at different listening positions. A loudspeaker coming close to this design goal, will reach the level of performance it is designed for even when placed in living rooms which are shaped and arranged differently.

The best Form follows function

The dipole 08 stand is an inertial vibration damper, fixing the motors of the drivers in space as rigid and free of vibration as possible. To achieve the mass needed for that purpose and to integrate the system equally well into the living room optically, natural stone was chosen as building material for the stand. With height of 160 cm and only 19 cm width of the front baffle, the system integrates very well into the living room as a stele-like object.

In this loudspeaker there are virtually exclusive those components vibrating, which are dedicated to radiate sound. These are the cones of the driver units only. The tall and narrow open baffle enforces a sound radiation distributed evenly over the entire spectrum, thereby minimizing lobing in the horizontal plane. Musical instruments and voices as well keep their typical timbre in every pitch. The listener is free to choose the recordings to listen to, without taking “the loudspeakers favourite music” into account.

The result is a Loudspeaker reproducing music and not itself

The absence of cavities and obstacles to sound propagation ensures a sound, which is freed from the loudspeakers thereby letting the music flow in its emotional expression and rhythm. While detail is audible in high resolution, it is not imposed on the listener. Musical detail is part of a homogeneous whole, which is felt and experienced in the whole living room.

Dipole 08 is not a Prototype anymore and has become a maturated system.