Soundstream Reference 705 Owner's Manual

REFERENCE 705

5/3 Channel

Power Amplifier

OWNERS MANUAL AND

INSTALLATION GUIDE

1

CONGRATULATIONS!

You now own the REFERENCE705 Amplifier, the product of an uncompromising design and engineering
philosophy. Your Soundstream REFERENCE amplifier will outperform any other amplifier in the world.

To maximize the performance of your system, we recommend that you thoroughly acquaint yourself with its
capabilities and features. Please retain this manual and your sales and installation receipts for future reference.

Soundstream amplifiers are the result of American craftsmanship and the highest quality control standards, and
when properly installed, will provide you with many years of listening pleasure. Should your amplifier ever need
service or replacement due to theft, please record the following information, which will help protect your
investment.

Serial # _____________________________________________
Dealer’s Name _______________________________________
Date of Purchase _____________________________________
Installation Shop ______________________________________
Installation Date ______________________________________

CAUTION!

Prolonged listening at high levels may result in hearing loss. Even

though your new Soundstream Reference705 sounds better than

anything you’ve ever heard, exercise caution to prevent hearing

2

TABLE OF CONTENTS

Features .........................................................................................................................4 - 5

REFERENCE Power Supply Design ....................................................................................6

Setting High Power/High Current .........................................................................................7

Selecting Crossover Modes .................................................................................................8

Selecting Input Modes .........................................................................................................9

Setting Coherent Stereo/Bridged Mono ...............................................................................9

Wiring (with Diagram) ........................................................................................................10

Installation and Mounting ...................................................................................................11

Level Setting ......................................................................................................................12

Crossover Adjustments ......................................................................................................12

LSE.Q Subwoofer Equalization Circuitry ...........................................................................13

Sample Systems .........................................................................................................14 - 17

Protection Circuitry & Troubleshooting ..............................................................................18

Service ...............................................................................................................................19

Specifications ....................................................................................................................19

3

Reference705

Handcrafted in the U.S.A.

Fault

High Power

High Current

C H 1

60-2 40Hz

240 -960 Hz

60- 2 40Hz

MONO

MONO

-ONE+

1-4KHz

C A U TI O N : DO NO T SW ITC H WHE N AM PLIFIE R IS TURNE D ON .

SU B C HA N N E L

Use H IG H C U R R EN T f o r S UB C H A NN EL loa d s a t o r b e lo w 1 o h m .

LSE.Q X-OVER LEVEL INPUTS

-TWO+

0.7-2.8 17-60

Q

BOOSTHzFRE Q

H IG H PO W ERH IG H C U R R EN T

30-60

2.5-0.04

Hz

VOLTS

LP

SUBWOOFER CHANNELS 3 + 4CHANNELS 1+ 2

SU B C H A N NE L

(N O N -BR ID G E A BLE)

+ L - - R ++12v GND REMOTE

X-OVER LEVEL INPUTS

1K-4K

240-960

60-240

2.5-0.1 60-240 2.5-0.1

Hz

VOLTS

(3-WAY)HzHP

* In 3 -W A Y x o ve r mod e , CH 1 & 2 be c o m e HIG H PASS, CH 3 & 4 be c o m e BAN D PA SS.

BO TH SWITC H ES S HO U LD BEIN THE S AM E PO SITIO N

HIG H PASS

M ID

60 -2 4 0H z

3-W A Y *

(1 -4 KH z )STER EO

+ L - - R +

C H A N N E LS 1- 4 SU B C HA N N E L

+ L - - R + - + - +

USE R IG H T C HA N NE L I NP UTS F O R
BR IDG ING C H AN N ELS 1 - 4.

SP EA KER C ON N EC TIO N DIA G RA M

+ L - - R +

X-OVER LEVEL INPUTS

L RL RL R

VOLTSHP

DE -

EM P HA SI S

IN PU T

SEL EC T

RE A R FILLXO V ERXO V ER

7K Hz LP
6d B/O c t

DESIGN FEATURES

• Uncompromising Design and Construction including mil-spec glass epoxy circuit boards and

high current custom gold-plated solid brass connections that will accept up to 4 gauge power/
ground wire.

• High Power/High Current Capability (subwoofer channel only) - Soundstream’s exclusive circuitry

permits customization of your amplifier to its particular application—High Current, for ultra-low
impedance loads (multiple subwoofers, less than 1 ohm) or High Power, for higher impedance
loads (1 ohm and up).

• Chassisink

incorporates multiple output transistors instead of a few for faster, stronger power delivery. The
transistors are directly sandwiched between the circuit board and the heatsink in a design called
ChassisinkTM to ensure cool, efficient amplifier operation.

• Staggered Asymmetrical Electronic Crossover - Continuously variable 2 or 3-way crossovers

with 12 dB/octave high pass and 24 dB/octave subwoofer low pass. In 3-way mode, bandpass can
be selected for midrange or midbass.

• Rear Channel De-emphasis - A circuit based on theater surround technology in which rear fill

information is rolled off at 6 dB/octave with a -3 dB point at 7,000 Hz to provide a more realistic

TM

Darlington Power Array - Soundstream’s “overbuilding” of the output section

4

listening experience (in 5 channel mode only).

• PowerGrid Power Supply Design - All power supply components are located near one another,

for the shortest possible current path and are connected by thick, wide PCB traces, which ensures
rapid, high current delivery. The entire power supply is isolated on one side of the circuit board
while the audio stage is located opposite it, guaranteeing minimal noise.

• Ultra-Low ESR Capacitance Bank - 24 miniature “stiffening” capacitors ensure rapid power

delivery for dynamic peaks. Multiple small input power capacitors are used to provide a lower ESR
(Equivalent Series Resistance), which means more power, faster.

• Smart Thermal Rollback - Most amplifiers shut off when they get too hot. In the unlikely event the

Reference705 reaches 85° C, it will gradually roll back its average power (without affecting the
dynamics). Once the amplifier has cooled off, it returns to full power output. If overheating should
continue, a second thermal sensing protection circuit will shut off the amplifier if the heatsink
reaches 95° C.

• Unregulated Power Supply - 4 ohm power ratings are measured at 12 volts, which means

substantially greater output in the real world when the vehicle is running, where voltages range
from 13.6 to 14.4 volts. Dynamic capability of the unregulated power supply is vastly greater than
that of a tightly regulated power supply.

• Fault Monitor LED on the front panel notifies you of a blown power supply fuse.

• 1/2 Ohm Subwoofer Drive Ability - The Reference705 subwoofer channel is designed to be stable

into any impedance, down to 1/2 ohm.

• Six Dual Discrete Class A Drive Stages - Over six times the drive current of most amps, which

guarantees maximum performance into any load.

• Drive Delay

TM

Muted Turn-on/off Circuit - A unique circuit which completely eliminates amplifier-

related turn-on/off noises.

• Flexible Input Sensitivity accepts voltages from 100 mV (40 mV on the subwoofer channel) to 2.5

V, which permits maximum output from the amplifier with virtually any source unit.

• Balanced Input Design for added immunity to noise caused by component and vehicle electrical

system interaction.

5

REFERENCE POWER SUPPLY DESIGN

The Reference705 employs an extremely efficient unregulated pulse-width modulated power supply.
Like the rest of the REFERENCE amplifiers from Soundstream, the Reference705 is rated at 12 volts
but is designed to take advantage of the additional voltage available when the vehicle is running.
The two major advantages of the unregulated power supply are:

• awesome dynamic power capabilities

• added continuous power with higher voltages (see chart below)

Because of the dynamic properties of most music, all audio components should be able to react
accordingly. Thanks to its unregulated power supply, the Reference705 can comfortably exceed its
rated power for dynamic portions of the music.

4 Ohm Sub Channel Watts

14.4 volts

12 volts

0 50 100 150 200 250

4 ohm Power

200 watts x 1 @ 12 volts

250 watts x 1 @ 14.4 volts

6