Rockville dB55, Руководство пользователя

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8
Settings
USING THE ELECTRONIC CROSSOVER - 4 CHANNEL MODELS
The four and five channel models feature separate crossovers for channels 1-2 and 3-4.
All the dB Series amplifiers feature 12dB per octave fully adjustable low-pass and high
pass electronic crossovers.
FOUR CHANNEL AMPLIFIER CONFIGURATIONS.
1. All four channels High Pass for internal component speakers in doors and rear decks.
2. Channels 1 and 2 High Pass for front component speakers, while channels 3 and 4
are wired to sub woofers.
3. Bridge channels 1 and 2 for single high power sub woofer channel. Bridge channels
3 and 4 for second high power sub woofer channel.
For Low Pass systems, set the CROSSOVER MODE switch to LOW PASS. Now the
knob marked LPF will control the low pass frequencies from 50Hz to 250Hz. A frequent
mistake 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 100Hz (the 12 o’clock position).
When using the amplifiers for component speakers or coaxial, you will want to set the
CROSSOVER MODE switch to HIGH PASS. The HPF control knob adjusts the high pass
frequencies between 60Hz and 1.2KHz. Do not attach tweeters directly to the amplifier
even in the high pass mode without a secondary passive crossover to protect them.
PASSIVE 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 to from the
lowest setting to 50Hz, this will act as SUBSONIC FILTER for all signals below above
the HPF frequency 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.
ADJUSTING THE SYSTEM
Once the system is operational, the first thing to do, is set all crossover points to
approximate settings. In the case of the basic sub woofer system Low Pass filter
crossover at 100Hz or so. Set the bass equalizer controls to 0 dB.
Now you should set the amplifiers Input Sensitivity adjustment. The knob accessible on
the side of the amplifier marked LEVEL adjusts the input sensitivity.
To adjust the input
sensitivity, turn the control using a small flat head screwdriver fully counter clock wise
to the minimum position. Do not apply any pressure while turning as this might break
the control unit. Adjust your radio volume level to maximum volume. Now turn the level
control on the amplifier clockwise towards the Maximum marking until audible distortion
occurs. When you begin to hear any distortion in the sound, back down one notch and
your amp is set. It is helpful to have a second person to help you set the gain.
When setting up a multi-amp system, set each amplifier’s gain separately. Start off with
the bass amplifier, then adjust the highs amplifier’s level control to match.
Once you are satisfied with the level control settings, use any equalizer controls to adjust
the system tonal level for personal preference. Keep in mind that after equalizing, you
may have to go back and reset the amplifiers level controls.
The level control of any car amplifier should not be mistaken for a volume control. It is a
sophisticated device designed to match the output level of your source unit to the input
level of the amplifier. Do not adjust the amplifier gain to maximum unless your input level
requires it.
If your unit has been professionally installed please do not change the gain settings set
by the installer, he is the professional!
Your system can also be extremely sensitive to noise when the LEVEL is set to maximum
and does not match your input signal. The gain adjustments need to be made only once
when first setting up the system.