Rockville dB55, Руководство пользователя

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9
SETTING THE CONTROLS:
AUDIO PREAMP INPUT
The dB Series amplifiers feature RCA pre amp inputs. Run RCA cables from your sound
source to the inputs of the amplifier. We suggest the use of high quality shielded RCA
patch cords to help reduce and eliminate unwanted electrical noise to your system. Use
good quality RCA interconnect cables. Cheaper cables usually have poor shielding that
can cause interference pickup.
Be sure to run the RCA cables on the opposite side of the vehicle that you used to carry
the power and ground leads of the amplifier.
USING THE BUILT-IN LOW PASS ELECTRONIC CROSSOVER
All the dB Series amplifiers feature 12dB per octave fully adjustable low-pass and high
pass electronic crossovers.
For Low Pass sub woofer systems, set the CROSSOVER MODE switch to LOW PASS.
Now the knob marked LPF will control the low pass frequencies depending on the model
anywhere from 50Hz to 250Hz. A frequent error made is setting the low pass frequency
too low, especially when using vented sub woofer enclosures. We recommend that for
most installations you do not set the frequency knob lower than 80–100Hz (the 12 o’clock
position).
When using the amplifiers for component speakers or co-axials, you will want to set the
CROSSOVER MODE switch to HIGH PASS. The HPF control knob adjusts the high pass
frequencies between 15Hz and 4KHz depending on the model. Do not attach tweeters
directly to the amplifier, (even in the high pass mode) without a secondary passive
crossover to protect them.
SUBSONIC FILTERING
For sub woofer installations with a passive LP crossover, you can set the amplifier’s
CROSSOVER MODE selector to HIGH PASS while setting the HPF knob from the lowest
setting to 50Hz, this will act as SUBSONIC FILTER for all signals below that setting. This
is especially useful for vented enclosures where the port tuning frequency falls below the
sub woofer tuning frequency to protect against sub woofer unloading.
Settings