A series of loudspeakers using the Smooth Frequency Response technology. SFR ensure a low frequency response with the smallest slope of bass characteristic, similar to transducers curve. SFR minimizes self-resonances related to the dimensions of the open baffle. It releases from room standing waves, compensated by the dipole propagation of low frequency. Room Gain Control system allows to obtain even characteristics, regardless of size or shape of the listening room.

The open baffle loudspeakers system, with a passive filters, realize a bass roll-off with minimum phase shift. Low-pass filter compensates for the open baffle through characteristic with the same slope. Consequently it is possible to linear sound reproduction from lowest frequency band, assuring a bass tone with the correct timbre.

Loudspeakers with dipole nature of sound propagation, excite room resonances in a limited range, which for a low frequency it causes strong surge of loudspeakers-room characteristic. It is very difficult to remove resonances in the listening rooms. The bandwidth of room resonance is small, of row a few Hz, which makes it difficult to operate the acoustic equalizers or passive bass traps. The quality of sound reproduction through the loudspeakers with omni-directional bass radiation pattern is related to the dimensions and shape of the listening room. The dipole design doesn’t have such disadvantage, the room resonances occur on minimum level, regardless of listening position. In the result there is even sound distribution throughout the room space, devoid of the bass dominant.

Loudspeakers drivers work in the open baffle at the lowest damping factor. Pulse characteristics are at the highest level. Lack of closed air volume inside of loudspeaker and additional resonant elements causes a correct transient response.

JAF loudspeakers are a combination of classical design loudspeaker of a narrow dimension with advantages of the open baffle. Loudspeakers have compact dimensions while retaining the equivalent of a large baffle width. They represents an acoustic system in open, non-resonant technology with dipole nature of sound propagation, in which the radiation of rear side cone is obtained by a slit or aperture in back side of enclosure. The SFR technology (Smooth Frequency Response) allows to create the open baffle loudspeaker with a low frequency range and high efficiency, without adverse effects of classical large, flat baffle design.  The acoustic slit provides a symmetrical dipole nature of the low frequency propagation, limiting the adverse room resonances. The width of the slit and resulting acoustic impedance is matched optimally, volume of air inside does not affect the transducers parameters. The interior doesn't require additional dampening of soft materials. The SFR open baffle technology reduces a wide spectrum of negative acoustic interactions with the room. The advantage is an accurate and coherent reproduction of the sound image for each of the ranges in terms of spatial and stereo.

Generally in JAF loudspeakers there are applied four dynamic, full-range transducers transforming frequencies of low and medium tones. It is a benefit due to the low value of the cone mass. A proper pulse answer and the correct transients reproduction are the advantage. High frequency range supports the magnetostatic transducer. It is characterized by a large surface and low mass of diaphragm. The result is a wide directivity and high sonic resolution. All transducers determine the concept of low mass and large cone surface. The result is a small excursion, limiting the distortion related to the non-linear work of suspensions.

The JAF crossover filters represent the general nature of the first order. Detailed characteristic is tune up to the open baffle technology with acoustic slit. Optimization of crossover filters is related to slope characteristics, compensation of the open baffle efficiency, baffle step effect, linearization of loudspeaker coils inductance. Using the first order passive filters in the open baffle design, compensates the phase shift at low frequencies. Thus it is possible to obtain a linear reproduce from the lowest band frequency, providing high fidelity bass tones.


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