Russound ACP-1DU 1 User Manual

5 Forbes Rd. Newmarket, NH 03857, USA

Tel 603.659.5170 • Fax 603.659.5388

e-mail: tech@russound.com

ACP-1DU

Instruction Manual

Specifications

• Power Rating: 126W, 42W RMS, continuous per channel

• Frequency Response: 20 Hz to 20 kHz

• Dimensions: 2-5/8” W x 1-3/4” H x 2-5/8” D

(fits standard double-gang junction box)

• Connectors: Removable modular snap type

Accepts up to 14 gauge wire

• Attenuation: 12 steps, including “off”

Total attenuation of 43dB

Warranty

The Russound ACP-1DU is fully guaranteed for a limited lifetime warranty from the date of original purchase against all defects in materials and workmanship. During this period, Russound will replace any defective parts without charge for either parts or labor. Contact Russound for a replacement. Proof of purchase may be required. For this warranty to apply, the unit must be installed and used according to its written instructions. Accidental damage and shipping damage are not considered defects under the terms of the warranty. Russound assumes no responsibility for defects resulting from abuse or servicing performed by an agency or person not specifically authorized in writing by Russound. Damage to or destruction of components due to improper use voids the warranty. In these cases, the repair will be made at the owner’s expense.

Russound sells product only through authorized Dealers and Distributors to ensure that customers obtain proper support and service. Any Russound product purchased from an unauthorized dealer or other source, including retailers, mail order sellers and online sellers will not be honored or serviced under existing Russound warranty policy. Any sale of products by an unauthorized source or other manner not authorized by Russound shall void the warranty on the applicable product.

Wall Mount Stereo Volume Control

with A / B Switch

Product Overview

The Russound ACP-1DU is a wall-mount UltraMatch

stereo volume control

combined with an AB-1.2 A / B source selector switch. This product allows you

local selection and volume control of one of two amplifiers (sources) through a

single pair of speakers. The ACP-1DU is ideal for residential or commercial appli-

cation, and can be used with 4 to 8 ohm speakers.

The AB-1.2 A / B switch is equipped with removable modular snap connectors

for ease of installation. These connectors may be pre-wired separately and sim-

ply plugged in when the ACP-1DU is installed in the wall box. The ACP-1DU

uses a Decora® style double-gang wall plate.

UltraMatch™

The UltraMatch™ Volume Control connects between the speaker outputs of an

amplifier or receiver and a pair of speakers. The UltraMatch™ volume control pro-

vides a method of matching the minimum output impedance of the amplifier or

receiver, in addition to adjusting volume. The volume is adjusted by attenuating

the amplifier signal output of the control to the speakers.

Jumper Settings for Impedance Matching

By determining the drive capability of the amplifier with a few simple calcula-

tions, the number of speakers the system can safely operate can be determined

as well.

The jumper must be set in a position that correctly multiplies the impedance of

the system to a level that is equal to or greater than the impedance of the ampli-

fier. The 1X setting allows the volume control to be used as a standard control.

The 2X, 4X, and 8X settings allow it to be used as an UltraMatch™ control. The

jumper setting can be determined using the following simple steps:

1. Determine the amplifier's minimum impedance. The amplifier's minimum

impedance is usually found following Wattage and Frequency Response in

the amplifier's specification page of the manual. It may also be listed on the

back panel of the amplifier near the speaker terminals. AC impedance is mea-

sured in ohms.

2. Identify the correct impedance-matching chart according to the amplifier's

minimum impedance. There are two impedance matching charts shown in

Figure 1, one for 8-ohm (also 6-ohm stable) amplifiers and one for 4-ohm

amplifiers. Choose the chart that describes your amplifier.

012345678910111213141516

0 - 1X 1X 2X 2X 4X 4X 4X 4X 8X 8X 8X 8X 8X 8X 8X 8X

1 1X2X2X4X4X4X4X8X8X8X8X8X8X8X8X

2 2X4X4X4X4X8X8X8X8X8X8X8X8X

3 4X4X4X8X8X8X8X8X8X8X8X

4 4X8X8X8X8X8X8X8X8X

5 8X8X8X8X8X8X8X

6 8X8X8X8X8X

7 8X8X8X

8 8X

Impedance Matching For 4 Ohm Amplifiers

4 Ohm Pairs

8 Ohm Pairs

Fig. 1 Impedance Matching Charts For UltraMatch™

012345678

0 - 1X 2X 4X 4X 8X 8X 8X 8X

1 2X4X4X8X 8X 8X 8X

2 4X8X8X8X8X

3 8X8X8X

48X

Impedance Matching For 8 Ohm Amplifiers

8 Ohm Pairs

4 Ohm Pairs

Example: The table on the bottom right shows an 8-ohm minimum impedance

amplifier with 1 pair of 4-ohm speakers and 3 pair of 8-ohm speakers. The chart

indicates the jumper setting should be set at 8X.

28-0029 Rev. 1

Wiring Instructions (Refer to Figure 3)

1. Strip about 1/4” of insulation from the ends of all wires to be connected

to the AB-1.2. If necessary, twist the exposed conductors to ensure that no loose strands exist.

2. Connect the leads from the “A” amplifier to the Amp “A” Input snap

connector, with the left (L+ and L-) and right (R+ and R-) wires inserted in the appropriately marked openings in the connector. Snap the lever down on the connector, making sure that the exposed bare wire is engaged.

3. Connect the leads from the “B” Amplifier to the Amp “B” Input snap

connector in the same manner as described in step 2.

NOTE:

To avoid problems with certain types of amplifiers employing bridging outputs or isolated grounds, the L and R (-) grounds are separate. If a 3 wire system or common ground amplifier is used, the L- and the R- inputs of the ACP-1DU should be jumpered together. If one channel ground is open, that channel will appear to drop out when the volume control is rotated. The L- and the R- connections are placed adjacent to enable this type of connection, and to reduce short circuits.

4. The ACP-1DU comes with the AB-1.2 Speaker Out connector prewired to the volume control Input connector.

5. Connect the left speaker L+ and L- wire leads to the corresponding marked openings in the volume control’s Output connector. Connect the right speaker’s leads in the same manner, observing channel and polarity identification.

6. Install the completed assembly in the junction box. Insert carefully to avoid excessive strain on the plugs. If necessary, pre-dress the wires for easier mounting.

CAUTION: Do not reverse the input and output connections.

CONSIDERATIONS

1. Make sure that your amplifier has adequate wattage for the number of speakers. Watts per channel divided by the number of pairs should equal or exceed the individual speaker’s minimum wattage requirements.

2. You must use an UltraMatch™ volume control for each pair of speakers.

3. Every jumper setting must be set on the same setting throughout the system.

4. A minimum speaker load of 4 ohms can be connected to the output of each UltraMatch™ volume control.

EZB CONNECTING BLOCKS

The EZB-1-SC and EZB-2-SC connecting blocks are Russound accessories that simplify connections of multiple volume controls and speaker pairs. The EZB-1SC is a neat, compact wiring device capable of connecting four volume controls to an amplifier's outputs. The EZB-2SC expands the EZB-1SC to another 4 volume controls. Multiple EZB-2SC's can be used to expand the system to sixteen volume controls.

8X 4X 1X-2X 2X-4X-8X 1X

Jumper Settings for Impedance Matching (continued)

3. Determine the impedance for each pair of speakers by referring to its manual.

4. Determine the total number of 4 ohm pairs of speakers. (rows on charts)

5. Determine the total number of 8 ohm pairs of speakers. (columns on charts)

6. Follow the appropriate row and column to determine jumper settings.

7. Set the jumpers to the appropriate X setting as shown in Figure 2.

Fig. 2 Jumper Settings On Circuit Boards

Fig. 3 ACP-1DU Connections with Speakers and Amplifiers

Amp/Receiver “A”

Speaker Cable

AB-1.2 Source Selector

Speakers

Speaker Cable

ALTx Volume Control

OUT

ATTENUATOR OUT

RUSSOUND INC AB-1.2

SPEAKER OUT

Speaker Cable

AMP A INPUT

AMP B INPUT

Speaker Cable

Amp/Receiver “B”