Troubleshooting - Infinity 311a Instructions Manual

I S ( .)
NSTALLATION AND ETUP CONT
SETTING DBO ™ (311a, 611a and 1211a)
The Dynamic Bass Optimizer (DBO) is used to
enhance low-frequency reproduction in a vehicle.
Conventional bass-boost circuits only increase
bass at a fixed frequency, and cause the amplifier
to consume considerable power. The DBO allows
you to adjust the frequency (20Hz – 80Hz) as well
as the boost level (up to 12dB; see Figure 14),
allowing you to fine-tune the bass in your system
to optimize performance.
For sealed enclosures, the DBO can be used
to enhance the lower bass region of sealed
enclosures.
For bigger/fuller bass, adjust the HP FREQ
between 35Hz and 45Hz; adjust the BOOST
control according to your preference.
For tighter-sounding bass, adjust the HP FREQ
between 45Hz and 55Hz; adjust the BOOST
control according to your preference.
For vented enclosures, the DBO should be used
as a subsonic filter to reduce overexcursion
of the woofers. Set the HP FREQ control 10Hz
below the tuning frequency of the enclosure
(e.g., 25Hz for a box tuning of 35Hz); adjust the
BOOST control to taste. This will conserve
amplifier power typically wasted on frequencies
below the tuned frequency of the enclosure.
For infinite-baffle applications, set the HP FREQ to
the speaker's Fs value (reducing overexcursion of
the woofer); adjust the Boost control to taste.
Figure 14. Frequency-response curves show
typical DBO control ranges.
DBO HP FREQ Control HP FREQ DBO BOOST Control
DBO HP FREQ Control HP FREQ DBO BOOST Control
(adjusts cut-off (adjusts cut-off (adjusts boost amount (adjusts boost amount
frequency) frequency) at cut-off frequency) at cut-off frequency)
dB 20Hz 100Hz dB
dB 20Hz 100Hz dB
0 0 12 12
-3 6
-3 6
-6 -6 0 0
-9 -6
-9 -6
-12 -12
-12 -12
20 80 Freq. (Hz) 20 80
20 80 Freq. (Hz) 20 80
STATUS LEDs
Clip: Indicates the amplifier is being overdriven,
and your speakers may be in danger. This
should blink only on musical peaks, and not
be on constantly.
Power: Indicates the amplifier is on.
Protection: Refer to "Troubleshooting" for specific
indications.
Figure 15. LED status.
BOOST BOOST
MIN MAX
MIN MAX
Freq. (Hz)
Freq. (Hz)
T
ROUBLESHOOTING
• PROBLEM:
No audio (POWER LED is off).
CAUSE and SOLUTION:
No voltage at BATT+ and/or REM terminals, or
bad or no ground connection. Check voltages
at amplifier terminals with VOM.
• PROBLEM:
No audio (PROTECT LED flashes every
4 seconds).
CAUSE and SOLUTION:
DC voltage on amplifier output. Amplifier may
need service; see enclosed warranty card for
service information.
• PROBLEM:
No audio (PROTECT LED is on).
CAUSE and SOLUTION:
Amplifier is overheated. Make sure amplifier
cooling is not blocked at mounting location;
verify that speaker-system impedance is within
specified limits.
• PROBLEM:
No audio (PROTECT and POWER LEDs flash).
CAUSE and SOLUTION:
Voltage less than 9V on BATT+ connection.
Check vehicle charging system.
• PROBLEM:
No audio (PROTECT LED is on).
CAUSE and SOLUTION:
Voltage greater than 16V or less than 8.5V on
BATT+ connection. Check vehicle charging
system.
• PROBLEM:
Distorted audio.
CAUSE and SOLUTION:
Input sensitivity is not set properly, or amplifier
or source unit is defective. Check INPUT LEVEL
setting, or check speaker wires for shorts or
grounds.
• PROBLEM:
Distorted audio (PROTECT LED flashes).
CAUSE and SOLUTION:
Short circuit in speaker or wire. Remove
speaker leads one at a time to locate shorted
speaker or wire, then repair.
• PROBLEM:
Music lacks "punch. "
CAUSE and SOLUTION:
Speakers are not connected properly. Check
speaker connections for proper polarity.
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