Audio T Verdict
The Lyngdorf SDA-2400 is a compact but seriously powerful stereo amplifier, delivering 200W per channel into 8 ohms and 400W per channel into 4 ohms.
It combines Lyngdorf’s Pulse Width Modulation output stage with a fixed 390kHz switching frequency, minimal feedback and a maximum output current of 40A.
Balanced XLR and unbalanced RCA inputs make it easy to use with a conventional pre-amplifier, while coaxial and optical inputs allow a compatible digital source with variable volume control to connect directly.
Signal-sensing standby, 12V trigger control and an included rack-mounting kit make it equally useful in a high-performance stereo system or as part of a larger multichannel installation.
There is no volume control, streaming, RoomPerfect or source switching from the front panel, but that focused design allows the SDA-2400 to concentrate entirely on delivering clean, controlled power.
Lyngdorf SDA-2400 Digital Stereo Power Amplifier
The Lyngdorf SDA-2400 is a high-power two-channel amplifier designed for stereo, bi-amplified and multichannel audio systems.
It delivers a quoted 200W per channel into 8-ohm loudspeakers and 400W per channel into 4-ohm loads, with up to 40A of output current available for demanding musical peaks.
Analogue RCA and balanced XLR inputs are joined by coaxial and optical digital connections, allowing the amplifier to work with a wide range of pre-amplifiers, streamers, processors and digital sources.
A Pre-Amplifier or Variable Output Is Required
The SDA-2400 is a power amplifier and does not include a volume control.
The connected pre-amplifier, processor, streamer or DAC must provide a properly configured variable output. Connecting a fixed-level source may cause the amplifier to play at or near maximum output.
200W into 8 Ohms and 400W into 4 Ohms
The SDA-2400 is rated at 200W per channel into an 8-ohm load and 400W per channel into a 4-ohm load.
This gives it the power required for larger listening rooms, less sensitive loudspeakers and music with substantial dynamic range.
A maximum output current of 40A provides additional control during demanding musical passages and when driving loudspeakers whose impedance varies significantly with frequency.
Power Is Only Part of Amplifier Matching
The wattage figure alone does not determine whether an amplifier is suitable for a particular loudspeaker.
Nominal impedance, minimum impedance, sensitivity, room size, listening distance and preferred volume should all be considered when matching the SDA-2400 to a system.
Lyngdorf Digital Amplification
The SDA-2400 uses a Pulse Width Modulation output stage with Lyngdorf’s switch-speed optimisation technology.
A fixed switching frequency of 390kHz and minimal feedback are used to achieve low and consistent distortion across the amplifier’s operating range.
The efficient amplification design allows substantial output power to be delivered from a chassis measuring just 73mm high, including its feet.
Low Distortion and Wide Frequency Response
Lyngdorf quotes a frequency response within ±0.1dB between 20Hz and 20kHz.
Total harmonic distortion plus noise is specified at 0.004% at 1W into 8 ohms and 0.006% at 1W into 4 ohms.
At higher output levels, the quoted figure is 0.02% at 100W into 8 ohms and 200W into 4 ohms.
117dB Signal-to-Noise Ratio
The SDA-2400 has a quoted A-weighted signal-to-noise ratio of 117dB, referenced to 200W into 8 ohms.
This helps keep background noise low, preserving quiet details and the contrast between subtle passages and large dynamic peaks.
Channel separation is specified at 96dB at 1kHz and 200W into 8 ohms.
Balanced XLR Analogue Input
A stereo pair of balanced XLR inputs allows connection to a compatible pre-amplifier, DAC, processor or streamer.
Balanced connections can provide improved resistance to externally induced noise, particularly when longer interconnects are required.
The balanced input has a quoted impedance of 10k ohms, with an input sensitivity of 2V RMS and an amplifier gain of 26dB.
Unbalanced RCA Analogue Input
A conventional stereo RCA input is provided for pre-amplifiers, streamers and DACs without balanced outputs.
The unbalanced input has a quoted impedance of 200k ohms and the same 2V RMS input sensitivity.
The RCA and XLR inputs feed the same analogue input path and should not be connected simultaneously.
Do Not Connect RCA and XLR at the Same Time
The balanced XLR and unbalanced RCA sockets are internally connected in parallel.
Use either the XLR input or the RCA input. Connecting both at the same time can introduce noise and may cause incorrect operation.
Coaxial Digital Input
The coaxial S/PDIF input accepts compatible two-channel PCM signals at up to 24-bit/192kHz.
This allows a compatible streamer, CD transport or other digital source to feed the SDA-2400 without using an external analogue interconnect.
The digital input stage uses a Wolfson WM8804 PLL transceiver, selected for its dynamic performance and tolerance of incoming clock jitter.
The Digital Source Must Control Volume
The SDA-2400 does not apply user-adjustable volume control to its digital inputs.
Only connect a digital source that provides a suitable variable output, with its volume initially reduced to a safe level.
Optical Digital Input
The Toslink optical input accepts compatible two-channel PCM signals at up to 24-bit/96kHz.
An optical connection provides electrical isolation between the source and amplifier, which can help prevent unwanted ground-related noise.
The best connection will depend on the output options and volume-control behaviour of the connected source.
Analogue or Digital Connection?
Use an Analogue Input When
- The source or pre-amplifier has a preferred DAC
- A conventional analogue pre-amplifier controls the system
- Balanced XLR connections are beneficial
- An analogue source is being used
- Zero additional digital-input delay is required
Use a Digital Input When
- The source has a properly configured digital volume control
- You want to keep the signal digital for longer
- A coaxial or optical connection is more convenient
- Electrical isolation through optical is useful
- The system has been checked for safe volume operation
The analogue inputs introduce no quoted internal signal delay, while Lyngdorf specifies approximately 0.6 milliseconds of delay through the digital inputs.
Manual Input Selection
A selector on the rear panel chooses between the analogue, coaxial and optical input options.
The selected connection remains active until the rear switch is changed manually.
The SDA-2400 does not provide automatic source switching, an input menu or remote-controlled input selection.
Automatic Signal Detection
Each input supports signal detection, allowing the amplifier to wake automatically when audio is detected on the selected input.
With the rear Power State switch set to Low Power, the amplifier returns to standby after approximately 30 minutes without a signal.
Standby power consumption is quoted at just 0.35W, while idle consumption is approximately 25W.
Front Status Indicator
The front-panel indicator glows steadily while the SDA-2400 is operating and flashes while the amplifier is in standby.
12V Trigger Input and Output
A 12V trigger input allows a compatible pre-amplifier, processor or streamer to control the SDA-2400’s power state.
A matching trigger output allows the control signal to be passed to another SDA-2400, making it possible to switch several amplifiers together.
This is particularly useful in multichannel installations containing several SDA-2400 power amplifiers.
Stereo and Multichannel Systems
The SDA-2400 can power the left and right loudspeakers in a conventional stereo system when connected to a suitable pre-amplifier or variable-output source.
It can also provide two channels of external amplification for a surround sound processor such as the Lyngdorf MP-40 2.1 or MP-60 2.1.
Multiple SDA-2400 amplifiers can be used where additional channels are required, with trigger daisy-chaining helping coordinate their power states.
Bi-Amplification
The SDA-2400 may be used within a suitably configured bi-amplified system, including selected installations using a compatible Lyngdorf TDAI amplifier.
Correct output routing, level matching, timing and loudspeaker connections are essential when combining different amplifier channels.
The loudspeaker must also provide separate, electrically isolated input terminals suitable for bi-amplification.
Remove the Loudspeaker Terminal Links
When a loudspeaker is actively powered by separate amplifier channels, the links between its high-frequency and low-frequency terminals must normally be removed.
Incorrect connections can damage the amplifiers or loudspeakers. Seek specialist advice before configuring a bi-amplified system.
Speaker Connections
The left and right speaker terminals accept suitable banana plugs or stripped cable with a conductor area of up to 5mm².
Correct polarity must be maintained by connecting the amplifier’s positive and negative terminals to the corresponding terminals on each loudspeaker.
Speaker cables should be fitted while the amplifier is switched off and disconnected from the mains supply.
Do Not Bridge the SDA-2400
The SDA-2400 cannot be converted into a bridged mono amplifier.
Connecting the speaker outputs together in an attempt to create a bridge-mode amplifier will damage the product.
Do Not Use High-Level Subwoofer Inputs
Lyngdorf specifically warns against connecting the SDA-2400’s speaker outputs to the high-level input of a subwoofer.
A subwoofer should instead be connected through an appropriate line-level output from the pre-amplifier, processor or source equipment.
Compact Low-Profile Chassis
The SDA-2400 measures approximately 450mm wide, 73mm high and 360mm deep, including its 13mm feet.
Its low-profile design makes it easier to accommodate within a conventional hi-fi rack or a larger custom-installed equipment system.
The amplifier weighs approximately 6.5kg and is finished in matte black anodised aluminium.
Rack-Mounting Kit Included
A rack-mounting kit is supplied with the SDA-2400, allowing it to be installed within a suitable equipment rack.
A mains cable and trigger cable are also included.
Lyngdorf specifies a heat-dissipation value of approximately 210 BTU, so suitable ventilation must still be provided.
Allow Space for Ventilation
Leave at least 5cm of free space around the amplifier and do not cover its ventilation openings.
Do not install it directly beside equipment that produces substantial heat without providing suitable airflow.
Lyngdorf SDA-2400 or TDAI-3400?
Choose the SDA-2400 When
- You already have a pre-amplifier or AV processor
- You need two channels of high-power amplification
- Balanced, RCA or digital inputs are required
- A multichannel system needs additional power channels
- Streaming and RoomPerfect are handled elsewhere
Choose the TDAI-3400 When
- You need volume control and source selection
- RoomPerfect room correction is a priority
- Built-in music streaming is required
- A complete one-box stereo amplifier is preferable
- Additional system configuration and processing are useful
The Lyngdorf TDAI-3400 combines similar quoted power with source selection, volume control, streaming, RoomPerfect and extensive audio processing.
Lyngdorf Products and Audio T Guides
Key Features
- Two-channel digital power amplifier
- 200W per channel into 8 ohms
- 400W per channel into 4 ohms
- 40A maximum output current
- Pulse Width Modulation output stage
- 390kHz fixed switching frequency
- Minimal feedback design
- 26dB amplifier gain
- 2V RMS input sensitivity
- 117dB A-weighted signal-to-noise ratio
- 266 damping factor at 100Hz into 8 ohms
- 96dB channel separation
- Balanced stereo XLR input
- Unbalanced stereo RCA input
- Coaxial digital input up to 24-bit/192kHz
- Optical digital input up to 24-bit/96kHz
- Wolfson WM8804 PLL transceiver
- Manual rear-panel input selection
- Signal detection on all inputs
- Automatic standby mode
- 0.35W standby consumption
- 12V trigger input
- 12V trigger output for daisy-chaining
- Banana-plug and bare-wire speaker terminals
- Rack-mounting kit included
- Trigger cable included
- Matte black anodised aluminium finish
- Designed and manufactured in Denmark
Frequently Asked Questions
Is the Lyngdorf SDA-2400 an integrated amplifier?
No. It is a two-channel power amplifier without volume control, source controls, streaming or RoomPerfect.
How powerful is it?
Lyngdorf specifies 200W per channel into 8 ohms and 400W per channel into 4 ohms.
What is its maximum output current?
The quoted maximum output current is 40A.
Does it have a volume control?
No. Volume must be controlled by a connected pre-amplifier, processor, streamer or DAC with a suitable variable output.
Can a streamer connect directly?
Yes, provided the streamer has a properly configured variable analogue or digital output. A fixed-level output must not be connected directly without separate volume control.
Does it include RoomPerfect?
No. RoomPerfect is provided by compatible Lyngdorf integrated amplifiers and processors, not by the SDA-2400.
Does it include music streaming?
No. A separate streamer, network player or streaming pre-amplifier is required.
Does it have balanced inputs?
Yes. It provides a stereo pair of balanced XLR inputs.
Does it have RCA inputs?
Yes. A stereo pair of unbalanced RCA inputs is provided.
Can the XLR and RCA inputs be connected at the same time?
No. They are internally connected in parallel, so only one analogue input type should be connected.
Does it have a coaxial digital input?
Yes. The coaxial input accepts compatible two-channel PCM signals at up to 24-bit/192kHz.
Does it have an optical input?
Yes. The optical input accepts compatible two-channel PCM signals at up to 24-bit/96kHz.
Does it support Dolby Digital or DTS through its digital inputs?
No surround decoding is provided. A connected source should output compatible two-channel PCM audio.
Does it automatically select an active input?
No. The required analogue, coaxial or optical input is selected using a switch on the rear panel.
Can it turn on automatically?
Yes. Low Power mode uses signal detection to wake the amplifier when audio is detected on the selected input.
How long before it enters standby?
With signal-detection mode selected, the amplifier enters standby after approximately 30 minutes without an input signal.
Does it have a 12V trigger?
Yes. Trigger input and output connections are provided, allowing several SDA-2400 amplifiers to be daisy-chained.
Can it be used in a home cinema system?
Yes. Each SDA-2400 can provide two channels of amplification for a compatible surround sound processor.
Can it be used for bi-amplification?
Yes, within a correctly configured system using compatible loudspeakers and suitable output routing.
Can it operate as a bridged mono amplifier?
No. Lyngdorf specifically warns that bridging the speaker outputs will damage the amplifier.
Can it connect to a subwoofer through the speaker outputs?
No. Lyngdorf warns against connecting the SDA-2400 to a subwoofer’s high-level input. Use a suitable line-level connection from the controlling pre-amplifier or processor.
Which speaker cable connections does it accept?
The binding posts accept suitable banana plugs or bare speaker cable with a conductor area of up to 5mm².
Is a rack-mounting kit included?
Yes. A rack-mounting kit is supplied alongside the mains and trigger cables.
What is the standby power consumption?
Lyngdorf specifies approximately 0.35W in standby.
How large and heavy is it?
It measures approximately 450mm wide, 73mm high and 360mm deep, including the feet, and weighs around 6.5kg.
Which finish is available?
The SDA-2400 is supplied in matte black anodised aluminium.
Why Buy From Audio T?
- Specialist demonstrations with your preferred music
- Pre-amplifier and source matching advice
- Loudspeaker power and impedance guidance
- Balanced XLR and RCA connection comparisons
- Digital-source and volume-control setup assistance
- Stereo and multichannel system planning
- Lyngdorf processor and TDAI matching
- Bi-amplification guidance
- Speaker cable and interconnect advice
- Rack and ventilation planning
- Part-exchange options on suitable equipment
- Ongoing system and setup support
Contact your local Audio T store to arrange a demonstration or discuss adding the Lyngdorf SDA-2400 to your stereo or home cinema system.