Directed Electronics A1004 Car Amplifier User Manual


 
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© 2004 Directed Electronics, Inc
CROSSOVER SETTINGS AND GAIN ADJUSTMENT
Your Directed Audio power amplifier needs to
be adjusted carefully to achieve maximum
performance. These are some guidelines to
follow when fine-tuning the amplifier.
For full-range and simultaneous
stereo/mono bass applications, the
crossover selection switch should be
set to FULL. If the amplifier is driving
your subwoofers, set the switch to
LOW, and for mid-bass/midrange
output, set to HIGH.
The crossover frequency control needs
to be adjusted to suit your particular
system. For subwoofer applications,
try and keep the setting low enough to
prevent image smearing (you should
not be able to hear male voices from
the subwoofer) but not so low as to
create a gap between the subwoofer
and the mid-bass/midrange speakers.
For mid-bass/midrange settings, try to
keep the setting low enough to keep
your sound stage in front of you,
without overdriving the speaker. It will
be to your advantage to spend some
extra time with this adjustment,
listening to familiar music or system
set-up discs to achieve the kind of
musical reproduction that you prefer.
The gain adjustment allows you to set
proper signal match for clean, quiet
amplifier operation. For full-range and
simultaneous stereo/mono bass appli-
cations, start by playing some music
you are familiar with. With the gain
adjustment on the amplifier in the
middle of its rotation, bring up the
volume on your head unit to the 3/4
volume setting or until you start to
hear distortion or clipping. If you hear
distortion before you reach the 3/4
volume setting of your head unit,
reduce the gain setting on the ampli-
fier and start to raise the head unit
volume again. When you can listen to
the music at or slightly above 3/4 on
your head unit without audible distor-
tion, slowly raise the gain of the ampli-
fier until distortion is heard, then back
off the gain until the distortion is not
audible. This setting will allow you to
reach full output with all but the
quietest of source material, while
avoiding excessive noise in the
system.
NNoottee::
Remember that the Directed ESP
®
amplifiers use a digital
gain control with a finite number of adjustment steps. A very
small adjustment may not cause any audible change in level.
The same procedure should be used for
adjusting the amplifier when the on
board crossover is set to LOW or HIGH,
but you will also have to take into
consideration the effect that gain
adjustment has on system frequency
response and imaging. Again, plan on
spending some time with music that
you know getting the gain and
crossover settings the way you like.
Test discs and analyzers may help with
this process, but in the end it's your
ears that count - listen to the music!