Product Overview
The Russound ACP-1DU is a wall mount UltraMatch
TM
stereo volume control
combined with an A / B source selector switch. This product allows you local
selection and volume control of one of two amplifiers (sources) through a sin-
gle pair of speakers, available in a Decora® style double-gang plate.
The volume control is ideal for residential or commercial application. It can be
used with 4 to 8 Ohm speakers.
The A / B switch is equipped with screw terminal modular connectors for ease
of installation. These connectors may be pre-wired separately and simply
plugged in. The interlocking feature assures that the connection is safe and
permanent. Connectors are packaged and supplied separately.
UltraMatch
™
The UltraMatch™ Volume Control you have just purchased con-
nects between the speaker outputs of an amplifier or receiver and a
pair of speakers.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 UltraMatch™ volume
control provides a method of matching the minimum output
impedance of the amplifier or receiver, in addition to adjusting
volume. It eliminates the need for a speaker selector or imped-
ance matching equipment. The volume is adjusted by attenuating
the amplifier signal output of the control to the speakers. All
Russound Volume Controls are manufactured using a high-quali-
ty autoformer design which provides long life, excellent frequen-
cy response, no heat build-up, and maximum power transfer
from the amplifier to the speakers. All Russound volume controls
conform to UL Standard 1492 First Edition, and for Canada
Certified to CSA Standard 22.2 No. 1-M94. This certification
assures that your volume control has been designed and tested
for safety.
8X
4X
1X-2X
2X-4X-8X
1X
8X
4X
1X-2X
2X-4X-8X
1X
8X
4X
1X-2X
2X-4X-8X
1X
8X
4X
1X-2X
2X-4X-8X
1X
8X
4X
1X-2X
2X-4X-8X
1X
8X
4X
1X-2X
2X-4X-8X
1X
X1
X2
X4
Jumper
Settings On
Circuit Boards
Russound UltraMatch™ volume controls eliminate the need for
a speaker selector. By determining the drive capability of the
amplifier with a few simple calculations, we can determine the
number of speakers the system can safely operate.
DETERMINING THE PROPER JUMPER SETTING FOR
IMPEDANCE MATCHING
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 imped-
ance of the amplifier. The jumper setting can be determined using the follow-
ing 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
measured in ohms.
2. Identify the correct impedance-matching chart according to the amplifier's
minimum impedance. There are two impedance matching charts, one for 8
ohm amplifiers and one for 4 ohm amplifiers. Choose the chart that
describes your amplifier. If your amplifier is 6 ohm stable, use the 8 ohm
chart.
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. (ex.
see fig 2)
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 and EZB-2 connecting blocks are Russound accessories that simplify
connections of multiple volume controls and speaker pairs. The EZB-1 is a neat,
compact wiring device capable of connecting four volume controls to an amplifi-
er's outputs. The EZB-2 expands the EZB-1 to another 4 volume controls.
Multiple EZB-2's can be used to expand the system to sixteen volume controls.
8X
4X
1X-2X
2X-4X-8X
1X
8X
4X
1X-2X
2X-4X-8X
1X
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
0
-
1X 1X 2X 2X 4X 4X 4X 4X 8X 8X 8X 8X 8X 8X 8X 8X
1
1X 2X 2X 4X 4X 4X 4X 8X 8X 8X 8X 8X 8X 8X 8X
2
2X 4X 4X 4X 4X 8X 8X 8X 8X 8X 8X 8X 8X
3
4X 4X 4X 8X 8X 8X 8X 8X 8X 8X 8X
4
4X 8X 8X 8X 8X 8X 8X 8X 8X
5
8X 8X 8X 8X 8X 8X 8X
6
8X 8X 8X 8X 8X
7
8X 8X 8X
8
8X
Impedance Matching For 4 Ohm Amplifiers
4 Ohm P
airs
8 Ohm Pairs
Fig 2 Impedance Matching Charts For UltraMatch™
0
1
2
3
4
5
6
7
8
0
-
1X 2X 4X 4X 8X 8X 8X 8X
1
2X 4X 4X
8X
8X 8X 8X
2
4X 8X 8X 8X 8X
3
8X 8X 8X
4
8X
Impedance Matching For 8 Ohm Amplifiers
8 Ohm Pairs
4 Ohm P
airs
Example: The table to the 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
X8
