SINGXER SA-2 Class-A Headphone & Pre-Amplifier
The Singxer SA2 is the highly anticipated successor to the Singxer SA1/SA1 v2, bringing a significant step forward in power, refinement, and design. Featuring a fully balanced Class A topology, premium components, and exceptionally high output capabilities, the SA2 is built for demanding headphones and critical listeners.
The SA2 delivers a major performance boost over its predecessor, with increased output power on both the balanced and single-ended outputs. It effortlessly drives high-impedance dynamic headphones as well as current-hungry planar magnetics.
| Marque: Singxer |
| Product Type: Amplificateurs de casque |
SINGXER SA-2 HEADHPONE AMPLIFIER
The Singxer SA2 is the next-generation evolution of the acclaimed SA-1 V2. It is a high-performance, fully analog Class A headphone amplifier and preamplifier built around a completely balanced and discrete circuit architecture. Compared to its predecessor, the SA2 features a refined circuit design with lower output impedance and a dramatically increased output power, making it suitable for even the most demanding headphones on the market.
Balanced Design
As the SA-2 is a headphone amplifier with a fully balanced design concept, it has made the greatest optimization for full balance. Therefore, the best way to use it is : balanced input and balanced output, followed by single-ended input and balanced output.
SA2 Compared to SA1v2
- Output power has been increased from 5.5 watts into 32 ohms on the SA-1 to 10 watts into 32 ohms , with a maximum output of 15 watts into a 20 ohm load . It supports headphones with a minimum load of 8 ohms.
- Through circuit optimization, ultra-low distortion can be maintained even at high power output;
- More efficient heat dissipation design, using copper block + aluminum alloy radiator design;
- Reduced the impedance of the balanced headphone amplifier output port, enhanced the current driving capability, and provided greater thrust;
- Optimized PCB routing, adjusted the DC bias design of the circuit, added DC servo design
- Added GND/LIFT mode switch
Pure Analog Signal Path
With no digital control circuitry, the SA2 avoids any EMI interference that could affect the audio signal. High-performance ROHM input transistors ensure ultra-low noise and excellent linearity.
The output stage uses a multi-stage current amplification design, similar to what is found in full-size power amplifiers. Each channel is equipped with high-current ON Semiconductor output transistors for very low internal resistance and powerful drive capability.
To ensure safe operation, the SA2 includes protection against:
- Overcurrent
- Overload
- Short-circuit
- Thermal conditions
- DC offset
- Turn-on delay
To ensure compatibility with all headphone types—from sensitive IEMs to high-impedance studio models—the SA2 offers adjustable impedance and source selection via front-panel switches:
- Input Select: RCA / XLR
- Headphone Output Impedance Mode: LOW-Z (low resistance) / HI-Z (high resistance)
Output impedance on the pre-outs remains low for optimal matching:
- Unbalanced RCA: 22.5 Ω
- Balanced XLR: 45 Ω
Optimized Matching for IEMs, Planars, and High-Impedance Headphones
Headphones differ greatly in how much power they need and how they react to the amplifier’s output impedance. The SA2 is designed to work seamlessly with a wide range, from ultra-sensitive in-ear monitors (IEMs) to high-impedance, full-size studio headphones, thanks to its front-panel controls and intelligent impedance design.
SA2 HIGH POWER HEADAMP
Handles Every Headphone with Ease
The Singxer SA2 is engineered to deliver effortless power to every type of headphone, from ultra-sensitive in-ear monitors to high-impedance studio models. Its high-current, fully balanced Class A design ensures even the most demanding planar magnetic or hard-to-drive headphones perform at their best, with tight bass, clear mids, and controlled highs. Adjustable impedance settings and high output power mean you can enjoy full volume and dynamic control without distortion, hiss, or strain, making the SA2 a versatile amplifier for any listening setup.
SA2 HEADPHONE OUTPUTS
Flexible Headphone Outputs for Every Connection
The SA2’s headphone outputs make it easy to connect any headphone. Use the 4-pin XLR or 4.4mm TRRS balanced outputs for maximum power and clarity, or the 6.35mm single-ended jack for classic headphones. Every connection delivers clean, precise, and dynamic sound, effortlessly.
SA2 VOLUME CONTROL
Smooth, Precise Volume Control
The SA2 features a high-quality ALPS potentiometer for ultra-smooth and precise volume adjustment. Every step is linear and reliable, giving you perfect control over your listening experience without distortion or uneven gain.
SA2 GROUND LIFT SWITCH
Ground-Lift Switch for Clean, Noise-Free Audio
The Singxer SA2 features a ground-lift switch to address hum and ground-loop issues that can occur in complex audio setups. By isolating the amplifier’s ground from the source equipment, it eliminates unwanted noise without affecting the signal quality. This ensures a pure, silent background, allowing your headphones to reveal every detail of the music with full clarity and dynamics. It’s a simple yet powerful tool for maintaining pristine audio in any system.
TECHNICAL SPECIFICATIONS
MEASUREMENTS
Independent measurements confirm that the Singxer SA2 delivers extremely low distortion, high output headroom, and an exceptionally quiet noise floor. Its fully analog, fully balanced design performs at a reference level in testing—perfectly matching the listening experience reported by discerning users.
| SPECIFICATIONS | |
|---|---|
| Product type | Headphone amplifier Preamplifier |
| Amplification type | Class A |
| Inputs | 1x Balanced XLR 1x Unbalanced RCA |
| Outputs | 1x Balanced XLR 1x Unbalanced RCA 1x Balanced 4.4mm jack headphone output 1x Balanced XLR 4-pole headphone output 1x Unbalanced 6.35mm jack headphone output |
| THD+N | Single-ended output： THD+N=1% |
| Noise level | 0.66µV @ Niveau de sortie max, SNR / DNR 147dB 300nV RMS @ Gain faible, A-Weighting, 20Hz-22kHz |
| SNR | 147dB |
| Headphone output power (per channel) - Balanced - Single Ended | Balanced: 600 Ω - 560mW Balanced: 300 Ω- 1120mW Balanced: 120 Ω- 2800mW Balanced: 60 Ω - 5500mW Balanced: 32 Ω - 10000mW Balanced: 20 Ω - 15000mW Balanced: 16 Ω- 13000mW Single Ended: 600 Ω -140mW Single Ended: 300 Ω - 280mW Single Ended: 120 Ω- 660mW Single Ended: 60 Ω - 2300mW Single Ended: 20 Ω - 3500mW Mono16 Ω - 18000mw |
| Gain levels | Unbalanced input, unbalanced output: low gain 0dB, high gain 12.8dB Unbalanced input, balanced output: low gain 6 dB, high gain 18.8dB Balanced input, unbalanced output: low gain -6db, high gain 6.8dB Balanced input, balanced output: low gain 0dB, high gain 12.8dB Input impedance : single-ended 33K ohm, balanced 20K ohm |
Input Sensetivity | Balanced input / Balanced output: High gain: 4.2V RMS ; Balanced input / Balanced output: Low gain: 18V RMS ; Single-ended input / Balanced output: low gain: 9V RMS ; Single-ended input / Balanced output: High gain: 2.1V RMS |
| Output impedance levels | Low-impedance output impedance is 1.4 ohms (balanced) and 0.7 ohms (unbalanced). High-impedance output impedance is 11.4 ohms (balanced) and 10.7 ohms (unbalanced) |
GENERAL | |
|---|---|
| Power supply | 100-240V AC, 50/60Hz |
| Dimensions | 234 x 170 x 46mm |
| Chassis material | Aluminum |
| Color | Black |
| Weight | 1.8kg |
| Conditionnement | 1x Singxer SA-1 V2 1x Power cable |
1 = Balanced Input XLR (Right)
2 = Balanced Input XLR (Left)
3 = Balanced Output XLR (Right)
4 = Balanced Output XLR (Left)
5 = Single Ended Input (Left)
6 = Single Ended Input (Right)
7 = Single Ended Output (Left)
8 = Single Ended Output (Right)
9 = Ground Lift
10 = On/Off Switch
11 = Fuse Holder
12 = Power Inlet
Singxer
Singxer is a Guangzhou, China-based company founded in 2011, known for designing and developing high-performance HiFi audio products such as DACs and USB audio interfaces. They have earned a strong reputation by leveraging their deep expertise in XMOS audio processing and focusing on measurement-driven design, using objective data to support their audio performance claims.
They offer a range of high-end audio equipment, including DACs (Digital-to-Analog Converters), USB Digital Interfaces: Products that convert USB audio to other digital formats with ultra-low jitter. Headphone Amplifiers and Power Amplifiers known for its smooth, deep, and analog-like sound.
Singxer Audio has evolved from focusing on components and OEM solutions to launching its own consumer-facing line of high-fidelity products.
