Cadence UNITED series Manual - page 4
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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 100 Hz or so. Set the
Bass Boost equalizer controls to 0 dB ( Flat Switch Position.)
Now you should set the amplifiers Input Sensitivity adjustment. The knob accessible on the side of
the amplifier marked INPUT GAIN adjusts the input sensitivity from 150mV to 8 Volts.
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.
USING THE ELECTRONIC CROSSOVER - 4 CHANNEL MODELS (VEGAS + CHICAGO)
The four channel models feature separate crossovers for channels 1-2 and 3-4. All the
United 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 FREQUENCY will control the low pass frequencies from 40Hz to 150Hz. 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 FREQUENCY control knob adjusts the
high pass frequencies between 50Hz and 500Hz. Do not attach tweeters directly to the
amplifier even in the high pass mode without a secondary passive crossover to protect
them. 500Hz high pass is not a frequency high enough for tweeters.
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 FREQUENCY KNOB to 40Hz,
this will act as SUBSONIC FILTER for all signals below 40Hz. 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.
MOUNTING THE AMPLIFIERS:
Choose a convenient mounting location with unobstructed airflow.
The United amplifiers feature four mounting tabs located at the amplifiers four corners.
Using the supplied screws and grommets, gently mount the amplifier in to position.
***
Do not over tighten the screws.
***
The United Series amplifiers are supplied with built-in fuses, never replace the fuse that the amp
came with, with one of a larger value.
We suggest you construct a Red wiring harness with 2 additional fuses. One fuse should be
located near the car battery. This fuse near the battery offers protection against damage from
short circuits to the car chassis between the battery and the amplifier. A second fuse closer to
the amplifier offers additional safety to the amplifier itself. This fused red power wire should be
attached to the amplifier power terminal marked
12V+
.
The wire harness should be made of red primary cable of at least 4 gauge for all United Series
amplifiers. The harness should terminate in a large ring terminal for connection directly to the
positive terminal of the car battery. Use a spade plug to attach the wire, which connects to the
amplifier location marked
12V+
.
A second black color wire of equal gauge should be used as a ground connection to a welded
chassis member. When connecting the ground wire make sure that there is no paint or other
insulator blocking a good ground connection. When installing multiple amplifiers, mount them
in close proximity so that they can all share the same ground point. Attach the black ground wire
to the amplifier screw terminal marked
Ground
.
We recommend that you use the Cadence AMPKIT4 or AMPKIT8 amplifier installation kits, which
contains all the cabling and accessories necessary for a good, reliable installation.
BATTERY
FUSE
GROUND
REMOTE
TURN ON
Terminal of
head unit
Installation Basics
Mounting and Wiring