Alpine 3555 User Manual

? FEATURES
@ 4/3/2 CHANNEL OPERATION
The 3555 can be used as:
a. 4-channel amplifier, producing 120W per channel into 4 Q.
b. 3-channel amplifier, producing 100W (4 Q) into channels 1 & 2, and 200W (4 Q)
into the third channel.
c. 2-channel amplifier, producing 200W per channel into 4 Q.
@ STATUS MONITOR
This indicator illuminates in green when the amplifier is on and operational. This light
will turn orange if any internal protection circuitry is activated.
@ ACTIVE DIVIDING NETWORK
A pair of built-in, switchable and independent electronic crossover networks at 80 Hz,
18 dB per octave, can be used to set up the amplifier for low-pass (subwoofer) or
high-pass (tweeter/midrange satellite) applications. These networks can also be
switched off to allow full-range signal amplification.
@ ACOUSTIC COMPENSATION CIRCUITRY
A selectable (Off or On) equalization curve can be added to the amplifier’s output
signal, compensating for the inherent non-linearities of the automobile interior. It
extends low bass response and eliminates mid-bass boominess, giving the low
frequency response of the audio system tightness and accuracy.
@ DUO-R& FEEDBACK CIRCUITRY
Alpine's proprietary Duo-Beta is a technologically advanced form of feedback circuitry,
Duo-Beta supplies low negative feedback throughout the audio frequency bandwidth
and very high negative feedback at DC. This stabilizes the amplifier, removes DC
offset, and offers excellent total harmonic distortion (T.H.D.) characteristics. !t also
provides low transient intermodulation distortion (T.I.M.), excellent slew rate, stability,
and musicality.
@ NO CURRENT LIMITING
Absence of current limiters in the audio section ensures low T.I.M., excellent transient
response, and superb sonic quality.
@ S.T.A.R. CIRCUITRY
The Alpine-developed Signal Transit for Accurate Response circuit topology improves
sonic properties by reducing interaction between different sections of the circuitry.
@ INPUT MODE SELECTOR
This switch allows the user to specify the input signal entering the amplifier.
@ INPUT CHANNEL SELECTOR
This switch allows the user to specify the input signal entering channels 3 and 4 of the
amplifier.

Alpine 3555 Specifications

Power Output

4-channel power output (max)	120W x 4
4-channel power output (into 4 ohms with 0.04% THD)	50W x 4
3-channel power output (into 4 ohms with 10% THD)	100W x 2 and 200W x 1
2-channel power output (into 4 ohms with 10% THD)	200W x 2

Audio Specifications

frequency response	10 Hz to 50 kHz (+0, —1 dB)
signal-to-noise ratio	105 dB (referenced to rated power)
input sensitivity (for rated power output)	100mV to 2V (500 mV at center detent)
input impedance	10k ohms Min.
speaker impedance	4 or 2 ohms (stereo), 4 ohms (bridged)
active dividing network frequency and slope	80Hz, 18 dB per octave
acoustic compensation effect	+5 dB at 40 Hz, —1 dB at 150 Hz

Power

power requirement	11 — 16V DC Negative Ground

Weight and Dimensions

dimensions (W x H x D)	263mm x 55mm x 300mm
dimensions (W x H x D in inches)	10-3/8" x 2-3/16" x 11-4/5"
weight	4 kg (8 Ibs. 13 oz)