Open baffle loudspeakers
- Open baffle speakers are inefficient in terms of the mechanical movement that is required to create a given level of sound. This not only applies to speaker cones but also to panel vibrations.
- Open baffle loudspeakers reproduce bass with less room interaction. It is more articulate than from box speakers.
- If dipole behavior covers the full frequency range, then the room response becomes perceptually masked by the direct sound.
- The radiation from the rear of the cone must not be absorbed, but the distance to the nearest reflecting/diffusing surface should be at least 3' (1 m).
- An open baffle circumvents the box problems of delayed radiation through cone and enclosure panels. They occur typically in the mid-frequency range and are difficult to suppress.
- Large panel radiators or long line radiators suffer from severe lobing at higher frequencies. It manifests in critical room and listener placement.
- Even though a dipole requires a 6 dB/oct boost towards low frequencies, it takes little power to drive it to maximum excursion at its lowest bass frequencies. Amplifier power could be an issue as frequency increases, where it requires higher cone acceleration to reach Xmax. Thus SPL is limited by driver volume displacement at the very lowest frequencies and becomes amplifier limited as frequency increases.
- Realistic bass levels can be obtained from dynamic drivers in open baffles, not from panels. For extreme SPL requirements the number of drivers could get very large and, therefore, below 50 Hz they are more economically replaced by sealed box subwoofers.
- At frequencies where a 8" driver would become directional it has wider frontal dispersion for an open baffle than if the baffle were closed in the back.
- Open baffle speakers reach deeper into the room and are less subject to the room response if their polar response is well behaved.
- ORION exemplifies open baffle loudspeaker design in terms of polar response control and dynamic range. It circumvents the limitations of large panel radiators and yields a small package.
- The low masses of the moving parts in an ESL, a planar magnetic, or a ribbon driver are necessary to generate useful sound pressure levels. The force generated by an electrostatic or planar magnetic motor is weak. Since SPL is proportional to air volume acceleration, and moving parts Acceleration is Force divided by Mass, the mass has to be lower if the force is too weak to generate sufficient acceleration. Furthermore, since excursion is limited with these drivers the radiating area has to be large to move a sufficient air volume.. These relationships seem to be difficult to grasp by audiophiles. Marketing departments and even some designers like to tout low mass as an inherent benefit giving greater "speed" or frequency response to their speaker, when it is only affecting sensitivity in SPL/W.
- It is difficult to screw up an open baffle speaker design to where it sounds worse than your typical box speaker.
You can discuss and study about open baffle for the next 5 years, but a minute of listening will do a lot more.I don't understand how this could possibly be a better option than an enclosure. It seems like you pointlessly lose efficiency and low end response in favor of... something. What am I missing here?
I don't understand how this could possibly be a better option than an enclosure. It seems like you pointlessly lose efficiency and low end response in favor of... something. What am I missing here?
The interact "less" with the room; meaning cause less standing waves and reflections, the backwave even works for spaciousness.