Rockford Fosgate PWR-54/58 - Manual (Page 5)

Manifold Vented Pole Piece – A vented pole piece by design ensures
adequate ventilation to cool the voice coil and maintain safe operat-
ing temperature. Our exclusive Manifold Venting technique prevents
air pressure build-up that causes the splashing of Ferrofluid out of the
voice coil gap.
Voice Coil – The construction of the voice coil is designed to
maximize the speaker's power handling. The wire used is high
temperature copper, wound in two layers on a black, anodized
aluminum former. The wire itself will withstand high temperatures
and the former will conduct the heat away from the coil.
Powder Coated Basket – The stamped steel baskets of the Punch
Power speakers are finished with a powder coat process. This good
looking finish helps reduce basket resonance, preventing basket
vibration from coloring the sound. Unrelated to the sonic perfor-
mance of the speakers, but equally important, the powder coating
used is environmentally friendly since no toxic chemicals are re-
leased into the environment during the finishing process.
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UNCH
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PEAKERS
Speakers are built in different sizes to optimize their performance in
different frequency bands. Crossovers are used to route the different
frequency bands for each appropriate speaker. There are two opera-
tional types of crossover, active and passive. An active crossover is
an electronic filter which comes before the amplifier and separates
the signal fed to different amplifiers in the system. A passive crossover
is positioned after the amplifier and separates the signal fed to each
speaker in the system. Each type of crossover offers its own advan-
tages and disadvantages. Active crossovers offer the accuracy and
flexibility needed for a sophisticated system and are used in expen-
sive multiple amp designs. Passive crossovers, such as capacitors,
resistors and inductors, allow the use of multiple speakers in a system
which can easily be expanded over time. We offer passive crossovers
with 6dB and 12dB per octave slopes. The 6dB per octave crossover
requires only one component and the gentle slope allows for smooth
transition between the speakers. The 12dB per octave crossover gives
the speaker better power handling capacity outside the pass band of
the crossover range.