Soundstream Technologies 414s, 644s owner manual BALANCED/UNBALANCED Input, Wiring, Balanced Input

•l INSTALLATION STEP 2 b

BALANCED/UNBALANCED INPUT

The REFERENCE6445 amplifier has the ability to accept either standard Unbalanced RCA signal inputs, or Balanced “Pro Audio” inputs with the use of the Soundstream BLTTH or BLT4N Balanced Line Transmitters or some other balanced line audio source. Before installing your system, you should decide upon which signal type you wish to run. There are advantages to both:

4 INSTALLATION STEP 3 a

WIRING

POWER AND GROUND

To ensure maximum output from your REFERENCE amplifiers, use high quality, low-loss power and ground cables. The REFERENCE amplifiers will accept up to 4 gauge power and ground cables. Determine from the chart below the minimum gauge power and ground wire for your application.

ADVANTAGES 1. Most preamplifier/ source

BALANCED INPUT

1.Improved Signal-to-Noise Ratio. (S/N Ratio)

2.Excellent noise cancellation characteristics.

3.Immune to noise radiated in the car audio environment.

I up to IO’ I up to 20

The REFERENCE644s amplifier’s signal input?. accept two ranges of input signal levels: 0.2 2.0 Vrms, or 0.5 - 5.0 Vrms for both Balanced and Unbalanced inputs. The input range switch position and level settings are dependent upon the preamplifier I source unit output signal level. For the best system Signal-to-Noise Ratio, we recommend that the input level controls be set as far down as possible (rotated counter-clockwise), while maintaining an acceptable level of output.

Usino the “Unbalanced” RCA inout

When using the Unbalanced RCA input. the RIGHT channel (channel 2) input signal switch MUST be in the “UNBAL” position. Also, when first installing the amplifier using this input configuration. we suggest that the remaining input signal switches be in the “UNBAL’ position as well. If YOU exuerience alternator whine or other installation noise with both switches in the ,IUNBAL” position. try movioa channels 1. 3 8 4 inout sianat switches t0

II II

tiemBAI This should remove any system noise due to installation.

Usino the “Balanced” RCA input

When using the Balanced 6.pin DIN input, both switches MUST be in the “BAY position. Also, we recommend that when using this input configuration, the “INPUT LEVEL” switch be in the “0-.55\$’position, and the gains on the amplifiers be set to “minimum” (rotated counter-clockwise). The system gains should then be adjusted on the BLTT* or BLT4” Balanced Line Transmitter, or other balanced line audio source. For the pin configuration. see the

diagram below:

7RAI- .-ANCFn.,.-

NOTE: The pin configuration shown in the diagram is the

view looking into the + L& Sjsna, balanced input jack

on the amplifier.

Read this, or sparks will f/y!

The Soundstream REFERENCE amplifiers have t$&nsive internal power supply capacitance. called the Ultra-Low ESR Capacitance Bank. Multiple small input jower capacitors act as an internal “stiffening capacitor. Because of the large amount of internal capacitance, there may be a sizable spark when connecting he power and ground lead to the amplifier for the first time. In order to charge he capacitor bank without a spark, we suggest you do the following:

1.Connect Ihe +12 volt cable to the amplifier and to the battery.

2.Connect one end of the ground cable to the chassis of the vehicle.

3.We have supplied a 150 ohm, 2 watt resistor with the amplifier. One leg of the resistor has been connected to the ground terminal of the amplifier.

4.To charge the capacitor bank, touch the loose end of the ground cable to the open leg of the resistor for at least 45 seconds.

5.Remove the resistor, and connect the ground wire.

\ /

CIRCUIT BREAKERS/FUSES

EXTERNAL

Like all audio components, the REFERENCE amplifiers must be fused near the battery. A fuse or circuit breaker must be located within 18” of the battery. This will prevent a fire in the event of a shaded cable. See the chart on the next page to determine the correct fuse value.

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