Derived from the granted resonator system of Helmholtz type and the RJ decompression system, the peripheral laminar decompression system constitutes an exceptional load of the driver in the very low frequencies improving speaker's braking, so transient rendering.
This system is similar in operation to the bass-reflex by the presence of two resonances framing an anti-resonance adjusted to the resonant frequency of the speaker in open air.
However the enormous progress made on the bass-reflex system is the coloring abscence (barrel's sonority) from 80 Hz to 300 Hz, by :
• Total acoustic filling of the enclosure increasing its apparant volume and avoiding all standing wave (coloring).
• The rear wave quickly exit the enclosure in phase with the front wave rolled through the cavity located immediately behind the speaker, this cavity acting as a low pass filter with very sharp cut (80 Hz to 30 dB per octave).
• The distortion obtained is extremely low compared to that obtained with a closed box.
• The cavity and its second baffle allows the rigorous phase of the tweeter with the boomer by spacial shifting from 3 to 5 cm (depending cutoff frequency).
1- Vent 2- Speaker
• Input impedance : 8 Ω
• Rated power : 90 W
• Sensitivity (for 1 W at 1 m) : 90 dB
• Amplitude frequency response curve : 30 to 35 000 Hz
Art & Acoustique Appliquée
3A patent filed November 25, 1976 n° 76 35 488
