OEM AW-IMP100WV — Impedance Matching Volume Control Manual

The AW-IMP100WV is an impedance matching volume control designed to compensate for the decreasing impedance that occurs when multiple pairs of speakers are connected to a single audio amplifier. It multiplies the impedance of the connected speakers to keep their combined load safe for the amplifier, protecting it from damage.

Key Features

• 100 Watts RMS power handling per channel
• 1X, 2X, 4X, and 8X impedance multiplier positions
• 12 volume positions including one Off position
• Protects amplifier by maintaining safe impedance
• 1X position allows use in ordinary (single-pair) applications
• Removable input/output terminal strip
• Stereo control (can also be used in mono applications)
• Suitable for residential and commercial applications
• Limited Lifetime Warranty

Installation Overview

1. Determine the desired impedance multiplication (see the selection charts below), then slide the multiplier switch on the front of the control to the desired position (behind the cover plate, if attached).
2. Connect the left and right channel outputs of the amplifier or receiver to the input of the volume control.
3. Connect the left and right channel outputs of the volume control to the speaker inputs.
4. Perform initial testing of the system at low volume settings on both the amplifier and the volume control(s).

Impedance Multiplier Selection

There are two methods for determining the proper impedance multiplication: the Chart Method (a lookup table, easiest since no calculator is required) and the Calculated method (more accurate, useful when speakers of different impedances are combined in one system).

Using the Charts

Select the chart that most closely matches the impedance of your speakers (8, 6, or 4 ohm — most installations use 8 ohm speakers). Move down the first column to the row matching the minimum impedance capability of your amplifier, then across to the column matching the number of speaker pairs you want to use. The resulting value is the multiplier switch position to select on each volume control in the system.

Similar charts exist for 6 ohm and 4 ohm speaker systems in the full manual — values shift toward higher multipliers as speaker impedance decreases. Combinations in the "light gray" zone of the original chart are slightly below the amplifier's minimum impedance but will likely work well.

Calculating the Multiplier Switch Position

1. Calculate the net impedance for all your speaker pairs.
2. Determine the minimum safe operating impedance for your amplifier (see the amplifier's owner's manual).
3. Divide the amplifier's minimum impedance by the net speaker impedance you calculated. The result is the minimum necessary multiplier value.
4. Round up to the next highest multiplier (1, 2, 4, or 8) unless you are within approximately 20% of a multiplier value, in which case rounding down may be acceptable.

Specifications

• Power Handling: 100 Watts RMS per channel
• Impedance Multiplier: 1X, 2X, 4X, 8X
• Volume Positions: 12 (including Off)
• Terminal Strip: Removable Input/Output
• Warranty: Limited Lifetime Warranty

Note: OEM assumes no liability for damage to any audio or electrical equipment due to improper setup, improper connection, or a volume control malfunction.