The Accent got new 1.5-liter 12-valve SOHC and 16-valve DOHC engines : the 1.3 continued modified with a Helmholtz resonator intake after 2003.
22.
Helmholtz resonators are used in architectural acoustics to reduce undesirable low frequency sounds ( standing waves, etc . ) by building a resonator tuned to the problem frequency, thereby eliminating it.
23.
Male cicadas make a noise to attract females, which has been described as " the sound of summer " . and can reach an earsplitting volume in excess of 120 Helmholtz resonators.
24.
In this sense, a loudspeaker enclosure with passive radiators emulates a mass-spring system, much like the helmholtz resonator devices ( bass reflex ports ) more commonly used to tune loudspeaker enclosures.
25.
Unique new 18 " x 8 " diameter 15-spoke aluminum wheels included a new noise quieting technology : a polypropylene " Helmholtz resonator " that encircled the center portion of the inside of the wheel.
26.
A Helmholtz resonator can have one port tuned to a single frequency, or several ports tuned to either a single or to multiple frequencies, with round port, slotted port, or even perforated construction.
27.
"' Giuseppe Donati "'( 2 December 1836 & ndash; 14 February 1925 ) was the inventor of the classical ocarina, a ceramic wind instrument based on the principle of a Helmholtz resonator.
28.
The pitch of a Helmholtz resonator is also affected by how far the air has to go to get in or out of the resonator; in other words, the thickness of the material the holes are cut in.
29.
Examples of resonating type bass traps include a rigid container with one or more portholes or slots ( i . e . Helmholtz resonator ), or a rigid container with a flexible diaphragm ( i . e . membrane absorber ).
30.
Each microphone and its associated loudspeaker was limited to the one frequency by placing the microphone inside a Helmholtz resonator fitted into the ceiling in a range of sizes which resonated over a wide range of the low frequencies which critics and musicians thought did not adequately reverberate in the hall . 172 channels were used to cover a frequency range of 58 Hz to 700 Hz, increasing reverberation time from 1.4 to 2.5 s in the 125 Hz octave band.
