a/d/s/ 335im - Manual (Page 6)

6 15
amplifier requirements
a note on power handling
Each 3-series speaker system requires a minimum of 20 Watts per channel to achieve reasonable
listening volumes in a moving automobile without clipping the amplifier. a/d/s/ recommends
150 Watts per channel as a maximum so as not to exceed the thermal or mechanical limitations
of the speaker system. Any amplifier between 20 watts and 150 watts per channel may be
used. If you choose to use an amplifier with more power than 150 Watts be very careful, you
can damage the speaker system if played too loud.
All a/d/s/ loudspeakers will produce reasonable volume levels in the automotive environment
using moderate amplifier power. However, the use of a low powered amplifier to try and attain
very high volume levels can lead to overdriving the amplifier. This will generate high distortion
levels which can easily damage loudspeakers, even when the amplifier’s rated power is far
below the maximum rated power of the loudspeaker.
As a rule, do not turn the volume up above the point where you hear distortion on musical
peaks from either an overdriven amplifier or mechanical noise from an overstressed speaker. For
the best performance and reliability, select an amplifier with slightly more than the maximum
power you are likely to need to generate the desired volume levels. This margin of reserve
power will ensure that the amplifier will not attempt to deliver more than its design allows.
Warning: Excessive sound pressure level can permanently damage your hearing. The maximum
volume levels attainable with a/d/s/ speakers, combined with high-power amplification, may
exceed safe levels for extended listening. When listening at high volume levels always use
hearing protection or turn it down!
mounting locations
There are many possible choices of mounting locations. The automobile factory locations will
usually dictate the speaker mounting position.
controls and connections
tweeter level control
The three position switch in the crossover box labeled low mid high adjusts the relative volume
of the tweeter with respect to the midrange. The mid position is referenced as equal output
from the midrange and tweeter. The hi position offers 3dB more output from the tweeter. The
low position is 3dB less output.
Adjust this control to your listening preference.
troubleshooting
symptom probable cause remedy
no output source or amplifier not turned on check source or amplifier and fix as
needed
audio input not connected or no check RCA connections and signal
output from source integrity, fix or replace as needed
protection circuit activated turn down volume. Protection will self
reset
speaker wires not connected check speaker wires and fix or replace as
needed
audio cycles on and off speaker damaged check system with known working
speaker and fix or replace as needed
thermal protection engaged check that amplifier has adequate
ventilation check speaker impedance
load
Loose or poor audio input check RCA, power and speaker
connections and fix or replace as needed
distorted output preamp volume set too high. check volume of preamp and adjust
exceeding maximum capability appropriately
of amplifier.
Impedance load to amplifier too low
check speaker impedance load, if below
1 ohm rewire the speakers to achieve a
higher impedance
shorted speaker wires check speaker wire connections and fix or
replace as needed
speaker not connected properly check speaker wiring and fix or replace as
needed. refer to the speaker wiring
section of this manual for detailed
instructions
speaker damaged check system with known working
speaker and fix or replace as needed
poor bass response speakers wired with wrong polarity check speaker polarity and fix as needed
causing cancellation at low frequencies
lack of stereo separation speakers wired with wrong polarity. check speaker polarity and fix as needed
stereo / bridge switch set to bridge set switch to stereo position
position
speaker connected across wrong
check that the speaker wires are not
output terminals connected to the bridged terminals and
fix as needed
source set to mono check source and adjust controls as
needed
analog and digital systems
one progress way
wilmington, ma 01887
usa
If you want to consult the factory, write or call our customer service department:
Customer Service Department
analog and digital systems, inc
300 wildwood avenue
woburn, ma 01801
ph 781.729.1140
fax 781.729.3535