Sonance UA 2-125 / UA 2-125 ARC 2-Channel DSP Amplifier Installation and Support Manual

Introduction

Thank you for selecting a Sonance UA 2-125 or UA 2-125 ARC amplifier. Sonance has over four decades of experience in premium distributed audio amplification. This amplifier has been precision engineered to provide maximum installation flexibility, low energy consumption, and audiophile sound in a compact form factor. Please take the time to carefully read through the manual, study the illustrations and system diagrams. This extra time can lead to trouble-free operation and continued musical enjoyment.

READ THIS SECTION IN ITS ENTIRETY BEFORE ATTEMPTING USE OF THIS AMPLIFIER.

Important Safety Instructions

Always follow these basic safety precautions when using your amplifier to reduce the risk of fire, electric shock, and injury to people or objects.

1. Read all the safety and operating instructions before operating the amplifier and retain them for future reference.
2. Adhere to all warnings and precautions listed on the amplifier and in the operating instructions.
3. Follow all operating instructions.
4. Never use the amplifier next to water.
5. Keep amplifier dry at all times.
6. Ventilation: Situate the amplifier so that its location does not interfere with its proper ventilation.
7. Heat: Situate the amplifier away from heat sources such as radiators, stoves, etc. (including amplifiers).
8. Grounding or Polarization: Take precautions so that these attributes are not defeated.
9. Power-Cord Protection: Route power supply cords so they will not be walked on or pinched by items.
10. Cleaning: Use 'canned air' or wipe the amplifier with a soft cloth. Do not use solvents, as they may damage the amplifier.
11. Non-Use Periods: Unplug the amplifier's power cord from the outlet when the amplifier will be left unused for a long period of time.
12. Moisture: Do not expose the amplifier to dripping or splashing. Do not place objects filled with liquids (e.g., vases, drinking glasses) on the amplifier.
13. Damage Requiring Service: Have the amplifier serviced by a qualified service technician when the power cord or power supply is damaged, dropped, the enclosure is damaged, something has spilled into the amplifier, it has been exposed to rain, or the amplifier is not operating properly.
14. Servicing: Do not attempt to self-service the amp. Contact Sonance Technical Support for servicing options.
15. Power Requirement: Do not connect the Sonance amplifier to the accessory outlet of any other component.

WARNING: The power mains plug serves as the amplifier's disconnect device. The disconnect device shall remain readily operable during operation. To ensure that the disconnect device is easily accessible, the user should not place the amp in a confined area during operation.

WARNING: Any changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

FCC COMPLIANCE STATEMENT: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. There is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected
• Consult the dealer or technician for help
• Reorient or relocate the receiving antenna
• Increase distance between the equipment and receiver
• Disconnect, then reconnect all cables

Product Description

The UA 2-125 | UA 2-125 ARC is a high power 2-channel audio amplifier equipped with advanced DSP functionality, capable of delivering an enhanced user experience with perfect matching to other Sonance speaker products. HDMI or S/PDIF (coaxial or Toslink) in addition to Stereo Analog Line Inputs and Line Outputs provide reliable connectivity. Specific equalization presets allow multiple speaker types and acoustic environments to easily be set-up and optimized within minutes. Features the SonARC Setup and Control App to link via short-range wireless connectivity to securely configure the device. The amplifier has automatic protection features to safeguard against overload, low impedance load, thermal overload and over/under power voltage situations.

Placement

The amplifier should be placed in a dry, non-condensing environment with ventilation. Locate the amplifier so it is completely isolated from temperature extremes, rain, snow, direct sunlight, and atmospheric contaminants. Do not locate the amplifier outdoors. Any moisture-related damage (such as from condensation) is not covered by the factory warranty. Locate the amplifier on a shelf or at the lowest place in a rack that has good circulation of fresh air to dissipate heat. The amplifier can be placed into a back box behind a television display or other enclosure with little ventilation as long as the ambient temperature does not exceed 35-degrees Celsius.

Unpacking and Record Keeping

Save the carton and packing inserts for future safe transport in case the amplifier is moved or requires shipping for repair. Before proceeding with installation, locate the serial number on the rear panel of the unit and note it here for future reference:

S/N: __________________________________________

Date of Sale: ___________________________________

Dealer Name: __________________________________

Contact Info: ___________________________________

Front and Rear Panel Connections

UA 2-125 Amplifier Panels

Audio Connector Panel

The UA 2-125 features an Audio Connector Panel with the following ports:

• 1. Setup Button: Pressing this button reactivates the internal radio if it has been turned off via the SonARC app.
• 2. IR Control Input: A 3.5mm IR input jack for connecting an infrared receiver for remote control.
• 3. Speaker Output: Removable speaker block connectors that accept up to 12-gauge wire.
• 4. COAX/Toslink Digital Inputs: For connecting digital audio sources (S/PDIF format).
• 5. Status LED: Indicates power presence and operational state.
• 6. RCA Stereo Input: For analog line input.
• 7. RCA Stereo Output: For line output.
• 8. Clip LED: Indicates when the amplifier is being overdriven.

Power Inlet Panel

The UA 2-125 features a Power Inlet Panel with:

• 9. AC Input: Connection for the removable power cord.

UA 2-125 ARC Amplifier Panels

Audio Connector Panel

The UA 2-125 ARC features an Audio Connector Panel with the following ports:

• 1. Setup Button: Pressing this button reactivates the internal radio if it has been turned off via the SonARC app.
• 2. IR Control Input: A 3.5mm IR input jack for connecting an infrared receiver for remote control.
• 3. Speaker Output: Removable speaker block connectors that accept up to 12-gauge wire.
• 4. HDMI Input: For connecting digital audio sources (HDMI ARC, eARC, CEC capable).
• 5. Status LED: Indicates power presence and operational state.
• 6. RCA Stereo Input: For analog line input.
• 7. RCA Stereo Output: For line output.
• 8. Clip LED: Indicates when the amplifier is being overdriven.

Power Inlet Panel

The UA 2-125 ARC features a Power Inlet Panel with:

• 9. AC Input: Connection for the removable power cord.

Powering the Amplifier

The UA 2-125 and UA 2-125 ARC feature a removable power cord. The amplifier will automatically start when power is applied. The Status LED will illuminate GREEN when connected to power. If the electrical service is subject to frequent sags, spikes or brownouts, a power conditioner designed for use with high fidelity equipment should be employed to protect the amp.

IMPORTANT: Do not plug the amp's power cord into a convenience outlet on any other audio or video component.

Source Connections

UA 2-125: Features stereo analog line input and S/PDIF (Coax and Toslink) digital input signal types. Connect to either the Coax or Toslink (optical), but not both. Only one can be used at a time. The UA 2-125 will automatically detect which one is being used.

UA 2-125 ARC: Features stereo line input and HDMI digital input signal types. Use a high-quality HDMI cable certified to HDMI 2.1 to connect to a TV. Plug one end of the HDMI cable into the TV using a port labeled "ARC" or "eARC", and plug the other end into the UA 2-125 ARC's HDMI IN port. Ensure that audio type is set to "PCM" in the settings of the connected TV. For most TVs, navigate within the TV settings menu to "audio" or "sound" to find digital audio output format ("Digital Audio Out", "Audio Format", or "HDMI Audio Format"). Select "PCM". Press "OK" or "Enter" to confirm the selection.

Speaker Connections

For optimal performance, use pure copper speaker wire that complies with fire rating codes. Be sure to check local codes governing wire that may be installed within walls or ceilings. The amplifier uses speaker block connectors that can accommodate up to 12-gauge wire.

Standard Stereo

For a standard speaker pair setup, connect speaker wire from the left speaker to the left portion of the speaker block connector, inserting the stripped end of the positive strand to the positive port and the stripped end of the negative strand to the negative port. Repeat these steps for the right speaker wire, connecting the positive to positive and negative to negative on the right ports of the speaker block connector. Plug the speaker block connector into the speaker output port on the amplifier.

Power Sharing Mode

UA 2-125 amps can be installed and set up for Power Sharing Mode to achieve a max 250W power by leveraging full power from a single channel output. This mode is recommended to support subwoofers or speakers that require high power. To deploy Power Sharing Mode for a pair of speakers, two amplifiers will be required. Power Sharing Mode for one subwoofer would require one amplifier.

Speaker Output Connections (Power Sharing Mode)

Speaker wire connection must be made to the positive and negative wire ports on the speaker block connector on the LEFT CHANNEL ONLY. Leave the right channel ports empty.

When connecting a source for a pair of speakers with a pair of UA amps in Power Sharing Mode, connect the Left input to the amp designated for the Left speaker and the Right input to the amp designated for the Right speaker to divide the stereo signal to the two amps that feed each stereo speaker. In the SonARC app, under Amp & DSP | Amplifier Output, set each amp Channel Configuration to "L Only to L Output" for the Left Channel Amplifier, and "R Only to L Output" for the Right Channel Amplifier.

IR Learning

This amplifier is equipped with a 3.5mm IR input jack that allows for command learning from third-party remote controls. Follow the steps below to teach the amplifier IR commands for functions such as volume control, power, and input selection.

1. Insert a 3.5mm mono cable into the IR jack labeled "IR" on the connections inlet panel.
2. Launch the SonARC app and select the amplifier from the listed amps.
3. Tap the IR LEARNING section from the list to access IR programming for power, volume, and mute.
4. Tap "learn" for a desired command. The indicator LED will blink Blue while waiting for the remote command.
5. Press the button on the remote while aiming at the IR emitter to program the button to perform the command.
6. Once the signal is received, the indicator LED will illuminate green.
7. REPEAT FOR ADDITIONAL COMMANDS: Continue teaching the amplifier additional commands by repeating the previous step.
8. Use the remote to verify that the amplifier responds to the newly learned commands.

NOTE: When an IR 3.5mm cable is inserted into the IR port, HDMI CEC control signals from the TV are disabled to prevent conflicts with the IR remote control commands. For most UA 2-125 ARC applications, the IR receiver is not needed. Your TV can send remote control commands over the HDMI cable using CEC. This works very well with most TVs. We strongly recommend using CEC control whenever possible. Be sure CEC functionality is turned on in your TV's settings and that the IR receiver is not plugged into the IR port.

Mounting the Amplifier

The UA 2-125 and UA 2-125 ARC amps feature a T-slot chassis design for flexible mounting and placement.

Mounting Bracket Installation

The included ambidextrous mounting brackets can be configured for either bottom-mount or top-mount (inverted) installation.

1. Prepare the Brackets: Begin by loosening the screws on each bracket arm (there are two screws per arm) to provide clearance for positioning. Do not fully remove the screws.
2. Insert Brackets into Chassis: Slide each bracket into the T-slot openings at both ends of the chassis. The brackets should slide smoothly into position.
3. Position for Mounting Orientation: For bottom-mount installation (amplifier right-side up): Position the bracket arms in the T-slot on the bottom of the chassis at both the front and rear ends. For top-mount installation (amplifier inverted): Position the bracket arms in the T-slot on the top of the chassis, ensuring the flat portion of the bracket arms will sit flush against the mounting surface when inverted.
4. Secure the Brackets: Once the bracket arms are properly positioned and all screws are aligned with the chassis T-slots, tighten each screw to secure the mounting brackets firmly in place.
5. Mount to Surface: Position the amplifier with the brackets flush against the desired mounting surface. Ensure adequate clearance for the connection panel and power inlet panel to accommodate all cable connections. Secure the amplifier to the mounting surface using appropriate screws through the bracket mounting holes (minimum four screws recommended).

IMPORTANT: Before mounting, ensure all audio and power connections have been made and verified as outlined in the previous sections. Verify that the selected location provides proper ventilation as outlined in the PLACEMENT section.

T-Nut Installation

The UA amplifiers include four T-Nuts that can slide into the T-slot chassis in any desired slot and in any desired orientation to attach to any universally compatible T-slot hardware. Use the screws from the included amp brackets to secure the T-nuts into position.

DIN Rail Installation

For DIN rail mounting applications, compatible DIN rail adapters can be used with the T-slot chassis design. DIN rail hardware and information is available online and is not specific to Sonance.

Protection Circuitry

The amplifier has a multi-stage protection system to prevent damage to your amplifier and speakers.

Amplifier Channel Protection

If a channel encounters a short-circuit or extremely low impedance, the amplifier will self-protect.

Status Indicator LED

• GREEN: Analog input selected
• ORANGE: Standby
• RED FLASHING: Protection state; amp overdriven/clipping
• BLUE: Setup mode; short-range wireless or IR learning
• WHITE: Digital input selected
• PURPLE: Mix selected

The status indicator always displays the present state of the amplifier, unless set to ten second timeout. These settings can be adjusted in the Sonance SonARC App under "General". Within the app, LED Level can be set to Low, Medium, or High, and LED Timeout can be set to Always On (default setting) or ten sec.

Clip Indicator LED

When being overdriven, audio peaks display as RED flashes. If this situation occurs, the amp is being overdriven and the volume control needs to be reduced until the peaks no longer cause illumination of the Clip Indicator.

SonARC App Guidelines

Detailed descriptions and setting information for the SonARC for Sonance UA Series App. Reference the guideline chart on the following pages for descriptions and explanations of the SonARC UA App settings and features.

General Page

Allows naming of the amplifier and the basic configuration of power saving Auto Sense operation, how long it waits before sleeping if no signals are present to be amplified, how long the LED indicators will illuminate (automatically turn off after a preset time or always on), if the BLE radio link is enabled (it is required for controlling the amplifier but can be turned off afterward).

Volume Page

Volume adjustments, limit setting, turn-on volume setting, and mute.

Inputs Page

Use the Input Trim setting to match the input sensitivity of the UA 2-125 to the maximum signal level of the connected source. Digital sources are almost always referenced to 0dBFS (Full Scale). Leave this set to 0dB unless 1) you know that the digital source has built-in attenuation, 2) you need to adjust relative source levels for mix mode, or 3) as directed by the Sonance tech support team. For Analog sources, the default input trim setting is 0dB and corresponds to a maximum analog signal level of 2Vrms. Each additional 6dB of Input Trim gain corresponds to a matching signal with half the amplitude:

• 0dB Input Trim gain: 2Vrms max signal
• 6dB Input Trim gain: 1Vrms max signal
• 12dB Input Trim gain: 500mVrms max signal
• 18dB Input Trim gain: 250mVrms max signal
• 24dB Input Trim gain: 125mVrms max signal

Do not set the Input Trim gain to a setting higher than needed to match your source signal level. Doing so can cause the input signal to be clipped, leading to severe distortion and potential speaker damage.

Line Output Page

Settings for managing line output behavior for applications like daisy-chaining multiple amplifiers for multiple pairs of speakers or outputting to an active subwoofer. Turn on or off volume tracking, adjust level trim, infrasonic filter, channel configuration, phase, and audio delay.

Amp & DSP Page

Amplifier Output -> Channel Configuration:

1. 2-channel stereo (L & R) mode (2 x 125 watts).
2. Single Channel Power Sharing (L) Mode (1 x 250 watts). For Power Sharing mode, the Left channel output delivers up to 250 watts into a 4ohm load. The Channel Configuration can be set for Sum Mono to L Output, L Only to L Output, or R Only to L Output (see Power Sharing Mode section of the manual for connection details). This setting allows for control of source channel routing to the Left Output. Use L Output settings to get 250w single channel power into a single 4 ohm load.

Output Trim

For most installations, you do not need to adjust the output trim in the SonARC App. Leave the output trim setting at 0dB (default) for stereo 8Ω or single channel (8Ω, 6Ω, or 4Ω) operation.

When driving stereo lower impedance loads, adjust the output trim in the SonARC App to ensure optimal performance:

DSP

DSP equalization curves may be applied to the audio signal to compensate the magnitude and frequency response as desired and the inbound audio signal can be delayed 30 milliseconds.

Sonance has an extensive library of DSP EQ curves and downloadable presets.

Downloading Presets from the DSP Library:

Tap "download" to browse hundreds of Presets for various Sonance and James speaker and subwoofer models. Sections within the library can be tapped to collapse and expand by product category. Select the desired preset file to initiate download. Tap the back arrow to return to the list of saved presets.

Loading Presets

Tap to select a profile from the list of stored presets, then tap "load" to load the DSP Preset.

Saving Presets

When making adjustments to a loaded DSP Preset profile, a loaded DSP profile can be named and saved to the Saved Presets list. Edit the name in the text field, tap "Save" and the profile will appear in the Saved Presets list for future recall.

Deleting Saved Presets

To remove DSP Preset profiles from the Saved Presets list, tap and hold the profile. A pop-up window will appear asking "Are you sure you want to delete the profile/preset?" Confirm the deletion by selecting "Yes", or select "Cancel" to keep the profile in the Saved Presets list.

Editing Presets

The SonARC app allows for robust editing within DSP presets. To edit, first download and load a DSP EQ Preset from the DSP EQ Library in the app. Once a preset is loaded, select "Edit" to access Parametric EQ, Frequency, Q/Bandwidth, Gain, Crossover, Tilt Control, Delay, and Limiter settings.

Parametric Equalization

Configuration for the ten bands of parametric equalization is available. Equalization filters may boost or cut the desired frequency with adjustable bandwidth filters. Each one can be individually turned on or off as required by selecting the EQ button and then toggling the on/off switch.

Crossover | Delays

When the amplifier is used to provide high and low passed signals to drive woofers and tweeters separately, crossover and tilt control can be adjusted. Delay compensation can be applied in time or distance units of measurement as required (up to 29.4ms, 32.8 feet, or 10 meters).

Troubleshooting

No Power

Issue: Audio Connector Panel status LED does not illuminate when AC cord is plugged into an outlet and the amp is switched on.

• Cause: AC cable is improperly seated either at the back of the amp or at the AC outlet.
• Solution: Verify that both ends of the power cable are securely seated.
• Cause: There is no AC current at the outlet.
• Solution: Securely insert the AC cord into another known working AC outlet.
• Cause: Amp is actually powered but is in standby mode. There is no active signal and status LED is dark because it is set to time out.
• Solution: Send an audio signal to the amplifier, or use the General page of the SonARC app to change the LED Timeout to Always On.

No Audio

Issue: Status indicator illuminated Green but no audio from speakers.

• Cause: Current selected source is not sending an audio signal into the amp.
• Solution: Verify that the source is powered on, operating and not in a muted or paused state.
• Cause: Audio interconnect cables are not pushed-in securely at the source, at the preamp and/or at the amp's input connectors.
• Solution: With the amp powered off, carefully reinsert each of the RCA connections at the source, and preamp/zone controller. Ensure RCA connectors are plugged into the amplifier's INPUT terminals, not the OUTPUT terminals.
• Cause: The line level interconnect cables are defective.
• Solution: Substitute another interconnect cable for the source to preamp.
• Cause: The speaker wires at either the output of the amp or at the speaker location are not securely connected.
• Solution: Reattach the speaker wires on the 4-terminal speaker block connectors. Verify amplifier output with a short piece of speaker wire and a known good speaker.
• Cause: Input / Source settings are mis-configured and the input signal is being ignored.
• Solution: Use the Input page of the SonARC app to properly configure the Input settings for the desired source. Make sure the source is set up as either a Default source or Secondary source. If set as the Default source, make sure there is not a signal on the Secondary source that is causing the Default source to be muted or ducked.

Channel Out

Issue: One channel of the amp does not have output.

• Cause: Line-level interconnect cable from the source to the affected amp channel is loose, disconnected or faulty.
• Solution: Verify that the interconnect cables are properly seated at both the amp end inputs and source end outputs. Disconnect both interconnects on the amp end (1L and 1R input connections on the amp). Connect the functioning channel's cable from the source to the non-functioning channel's input jack on the amp (for example: if 1L is faulty, connect 1R's cable to the 1L input jack and test). Test playback to see if the speaker connected to the non-functioning channel works. If the affected channel is now working, the problem could be with that channel at the source or with the interconnect cable for the non-functioning channel. Replace the affected channel's interconnect cable and retest. Test source on another audio system to confirm channel outputs are functioning. Check coax, Toslink and HDMI connections as appropriate to model.
• Cause: Speaker wire leading out to the channel is loose, disconnected or faulty.
• Solution: Verify proper connection of the speaker wire at amp end and speaker end. If the channel is still inoperative, disconnect the speaker wire from the non-functioning channel at both the amp end and speaker end. Connect a new, test speaker wire from the affected amp channel output to the speaker or to a new, test speaker. If the affected channel is now working, the problem must be the speaker wire; replace with a new speaker wire. If the affected channel is still not working, the affected channel in the amp could be defective; contact Sonance Technical Support for next steps.

Protect Mode

Issue: Status Indicator LED is flashing RED.

• Cause: The amplifier is in an over-temperature condition due to overload.
• Solution: Allow the amplifier to be sufficiently cooled until the Status LED returns to ORANGE, BLUE, GREEN, or WHITE. Ensure that the amplifier is placed in a location for proper ventilation.
• Cause: The amplifier receiving an over-current from short-circuited output wiring or too low output impedance load being driven.
• Solution: Remedy the shorted output. Check all wiring and speakers to ensure no shorts are present. Disconnect from AC Power before attempting to fix and reconnect the wiring.
• Cause: The amplifier Output Channel Configuration is set up for Power Sharing Mode in the Amplifier & DSP page of the settings.
• Solution: Use the Amp & DSP page of the SonARC app to change the Channel Configuration to either Stereo 2-ch or Mono 2-ch.

Warranty

Sonance warrants to the first end-user purchaser that this Sonance-brand product (Sonance UA 2-125 or UA 2-125 ARC), when purchased from an authorized Sonance Dealer/Distributor, will be free from defective workmanship and materials for a period of Two (2) years from the date on the original sales receipt or invoice or other satisfactory proof of purchase.

Exclusions: The warranty is in lieu of, and exclusive of, all other warranties, express or implied, including implied warranties of merchantability, fitness for use, and fitness for a particular purpose. No one is authorized to make or modify any warranties on behalf of Sonance. Sonance shall not be liable for consequential, incidental, economic, property, or personal injury damages arising from the product.

Obtaining Authorized Service: To qualify for the warranty, contact your authorized Sonance Dealer/Installer or call Sonance Customer Service at (949) 492-7777 within the warranty period. Obtain a return merchandise number (RMA) and deliver the Product to Sonance shipping prepaid, along with proof of purchase.

Warranty Process: Follow troubleshooting instructions in this manual or work with your Sonance dealer. Sonance provides a 2-Year Limited Warranty to the original owner with proof of purchase from an authorized Sonance dealer. The warranty does not cover shipping charges back to Sonance or the use of the product in an unapproved environment or application.

To initiate a warranty claim:

1. Contact Sonance Technical Support with a description of the fault, the amplifier's serial number, and the date of purchase from an authorized Sonance dealer at: technicalsupport@sonance.com
2. Sonance Technical Support will follow up and may request additional troubleshooting.
3. Sonance Customer Service will follow up by email. Provide a scanned copy of your sales invoice to document warranty status.
4. Sonance Customer Service will provide an RMA number to be included on the shipping label. Send the amplifier back in its original factory carton. Write the RMA # on the shipping label, not directly on the product carton.

Contact Sonance at: https://www.sonance.com/company/contact

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