a/d/s/ 335im Amplifier requirements, Troubleshooting, Mounting locations, Tweeter level control

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!

troubleshooting

symptom	probable cause
no output	source or amplifier not turned on
	audio input not connected or no
	output from source
	protection circuit activated
	speaker wires not connected
audio cycles on and off	speaker damaged
	thermal protection engaged
	Loose or poor audio input
distorted output	preamp volume set too high.
	exceeding maximum capability
	of amplifier.
	Impedance load to amplifier too low
	shorted speaker wires
	speaker not connected properly

remedy

check source or amplifier and fix as needed

check RCA connections and signal integrity, fix or replace as needed turn down volume. Protection will self reset

check speaker wires and fix or replace as needed

check system with known working speaker and fix or replace as needed check that amplifier has adequate ventilation check speaker impedance load

check RCA, power and speaker connections and fix or replace as needed

check volume of preamp and adjust appropriately

check speaker impedance load, if below 1 ohm rewire the speakers to achieve a higher impedance

check speaker wire connections and fix or replace as needed

check speaker wiring and fix or replace as needed. refer to the speaker wiring section of this manual for detailed instructions

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.

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	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

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