EMPHASER EA490-200, Installation & Operating Manual

Page: 15 / 32

15
Subwoofer Low-Pass Frequency („SUB FREQ.”)
Ideally, the low-pass (LPF) cut-off frequency for the subwoofer should be set
between 50 to 90 Hz. The actual setting should be 'played by ear', i.e. set the
„SUB FREQ.” control in such a way that the bass reproduction is stiff and rich,
while still delivering a good and solid low-end extension.
3.2 Input Sensitivity Settings („LEVEL”)
To reach a maximum noise-free dynamic headroom from each individual
head unit/amplifier/speaker combination, it is important to set the respec-
tive input sensitivity controls („LEVEL”) correctly. On the one hand the sensi-
tivity settings determine the actual signal-to-noise ratio, on the other hand the
sensitivity setting also controls the maximum distortion-free SPL (sound pres-
sure level) possible with a specific car audio system.
3.2.1 Tips for Appropriate Sensitivity Settings
Before you start, all tone controls (Bass, Mid, Treble) and all fader and ba-
lance controls on the head unit have to be set to neutral or center position. The
„Loudness” function must be deactivated.
Turn both satellite „LEVEL” controls (Front and Rear) on the amplifier counter-
clockwise to their minimum positions. Turn-on your head-unit and keep the
volume control to the minimum! Press the „DOWN” button of the sub remote
control unit until you have reached zero level.
Now you set the volume control of your head-unit to approximately 3/4 of
full volume, while playing a dynamic track from a CD. Slowly increase the
sub channel level control by pressing the „UP” button until you can just ab-
out hear distorted bass sounds. Now you reduce the main volume level on
the head-unit to a medium listening level.
Now you start turning up the FRONT satellite „LEVEL” control clockwise,
until you have reached a good tonal balance between the front satellites and
the sub channel, a slight forwardness of the bass range should be preferred,
as this will be compensated later by normal driving noises.
Now you turn up the REAR satellite „LEVEL” control clockwise until you feel
that you have reached an appropriate sound level in the back of the car, so
that the total sound reproduction becomes smooth and homogenous.
Finally you should fine-tune the LPF cross-over frequency on the amplifiers
„SUB FREQ.” control.
Obviously, it is also possible to make a fixed sub channel setting by first set-
ting the desired subwoofer level on the remote „SUB LEVEL CONTROL”
and then unplugging the remote cable from the amplifier. The last sub level
setting will be automatically stored by the amplifier.
EA490200 Manual 28.07.2000 16:11 Uhr Seite 15