Russound D250LS — 2-Channel Power Amplifier with Local Source Switching Manual

Full Installation Manual for the Russound D250LS 2-Channel Power Amplifier with Local Source Switching — a distributed audio amplifier that automatically overrides zone speakers with a local source (TV, PC, etc.) via line, video, or 12V trigger inputs.

Product Overview

The Russound D250LS is a 2-channel power amplifier with automatic local source switching capability. It allows a local source (e.g., a PC or TV in the bedroom) to automatically override the speakers in that zone of a distributed audio system, using a variety of input/trigger options.

The D250LS is rated at 50 watts per channel into 8 ohms and 75 watts per channel into 4 ohms. With the Stereo/Bridge Mono switch in the Bridge Mono position, both channels combine for a higher-powered mono output rated at 150 watts into a single 8-ohm load. Each output channel incorporates protection circuitry for safety and reliability.

Thermal Protection

All Russound amplifiers include circuitry to safeguard against thermal overload, which can engage after extended high-volume operation without adequate ventilation and/or when speaker impedances are below the amplifier's minimum. If this occurs, turn off the amplifier, verify speaker impedance is above the minimum rating, check for adequate ventilation, and power back on once the unit has cooled.

Protection Circuitry

All Russound amplifiers include circuitry to safeguard against short-circuit conditions, which can also be caused by a faulty speaker. If this occurs, turn off the amplifier and check speakers for short circuits.

Front and Rear Panel Features

• Power LED: Lights red on power-on; lights amber in standby.
• Power Switch: Turns the amplifier on/off but does not disconnect main power — unplug the power cord to fully disconnect.
• Line Input: A sensing input that activates the amplifier when an audio signal is present. Only the Left input is used in bridged mode.
• Video Input: A sensing input that activates the D250LS when a video signal is present.
• Gain Controls: Left and Right controls independently adjust sound level per channel; only the Left control is used in bridged mode.
• Delay Time: Muting delay adjustable from about 5 seconds to 4.5 minutes. When no audio signal is present, this delay automatically switches the amp back to Default input mode.
• 12VDC Trigger In/Out: The Trigger In controls switching from the default input (distributed audio system) to a local source; delay and audio sensing are bypassed when used. Trigger Out provides 100mA at 12V max to drive other triggered devices.
• Stereo/Bridge Mono Switch: Sets the amplifier channels for stereo or bridged mono operation.
• Default Input: A pass-through input for the whole-house system — if no signal is present on Line In or Amplified In, Default Input connects directly to the A and B speaker outputs.
• Amplified In: A sensing input used to amplify a high-level signal from a small amplifier or TV.
• Speaker A/B Outputs: Wired in parallel to the amplifier output. Minimum load in stereo mode is 4 ohms — drives up to 2 pairs of 8-ohm speakers or 1 pair of 4-ohm speakers. Minimum load for bridged mode is 8 ohms, Speaker B only.
• Fuse Receptacle: Holds a replaceable fuse (T3.15AL 250V) for AC power input.
• AC Input: Autoswitching 100–125VAC 60Hz (North America) or 220–240VAC 50Hz (Europe); accepts a 3-prong IEC 320 connector with a detachable 3-terminal power cord.

Installation Options

The D250LS can be set on a tabletop, wall-mounted with screws or hook and loop tape, or rack-mounted with included ears — either one unit in a 1U space or two units in a 1U space.

Wall Mounting

The amplifier comes with two wall mounting brackets and attachment screws, with two attachment locations on each side for more mounting options. Hook and loop tape can also be used.

Rack Mounting

For a single amplifier in a rack space, use the long ear and one wall-mount bracket, mounting to either side of the rack space. For two units in one rack space, use the flat plate to support and connect them, with one wall-mount bracket on each outer side. When mounting two units together, the small side ventilation slots will face each other in the middle of the rack space — ensure the top panel ventilation holes remain unblocked to avoid overheating.

Local Source System Configuration

The D250LS can be used as a single-source two-channel zone amplifier, or as a local-source amplifier that automatically switches between a default source (e.g., a whole-house audio distribution system) and a local source (e.g., a TV in the bedroom or a PC in the office). Connect the local source via A/V RCA cables (Line Outputs, Video, Right/Left) with optional video sensing, and the amplified input from the audio distribution system; amplified output feeds 4–8 ohm room speakers via speaker cable.

Bridged Operation

In bridged mode, the left and right channels combine for a higher-powered mono output. Turn off power to the amplifier and connect an 8-ohm minimum load to the Speaker B output. Following the Bridge Mode markings (in red) on the back of the amplifier: connect the negative (–) lead of the speaker cable to the R+ terminal, and the positive (+) lead to the L+ terminal. Set the Stereo/Bridge Mono switch to Bridge Mono, connect the Line In feed from a source to the Left Line In connection only, and restore power.

Dual Unit Setup

The D250LS can be used side-by-side with the optional rack mounting kit, making it easy to add amplification to two controllers or two zones (e.g., on a Russound MCA-C5 controller). A typical configuration uses two D250LS amps connected to an MCA-C5 on zones 7 and 8: one amp in bridged mode powers an outdoor zone (8-ohm speaker), while the other powers a pair of 4–8 ohm speakers in normal operation.

Technical Specifications

Warranty

The Russound D250LS Amplifier is fully guaranteed against defects in materials and workmanship for two (2) years from the date of purchase. During this period, Russound will replace defective parts and correct defects in workmanship without charge for parts or labor.

The warranty applies only if the unit is installed and used per its written instructions, and service must be performed by Russound with prior written permission (unit returned at owner's expense). The warranty does not cover damage from abuse, accident, misuse, negligence, or improper installation; power surges and lightning strikes; normal wear and maintenance; altered or modified products; or products with removed/defaced identifying numbers. Russound products purchased from unauthorized dealers, retailers, or online sellers are not covered.

For repairs, call Russound at (603) 659-5170 for a Return Authorization number before shipping to: Russound, ATTN: Service, 5 Forbes Road, Newmarket, NH 03857.