SCL Satri Circuit Laboratory HDA-5520 MK2 Headphone Amplifier
Product code:SCL Satri Circuit Laboratory HDA-5520 MK2 Headphone Amplifier
Could not load the receipt status
Headphone amplifier powered by AA batteries
Bringing out the true potential of headphones with current-driven design
The SCL Satri Circuit Laboratory HDA-5520 MK2 is the successor to the early HDA-5520 model, which gained popularity overseas. The internal circuitry has been significantly upgraded, resulting in clearer and deeper sound. This unit features current output, allowing your headphones to be driven with current for more detailed and information-rich playback. It is a headphone amplifier that lets you experience the true performance of your favorite headphones.
Clear, noise-free power and high convenience
One of the main features of the HDA-5520 MK2 is that it operates on **battery power (12 AA batteries)**. This eliminates any concern about power supply noise, delivering extremely clear and transparent sound. With a single battery charge, it can operate for about 40 hours, offering high convenience without restrictions on portability or placement.
Versatile driving methods for optimal performance
This unit supports both voltage output and current output. Sealed headphones and earphones work well with current drive as impedance changes are minimal, reducing distortion and minimizing the influence of cables while providing richer detail. On the other hand, open-back headphones, which experience larger impedance variations, can switch to voltage drive to deliver optimal audio performance.
Satri Circuit Technology for precise playback
Based on SCL’s proprietary Satri circuit technology, this design achieves extremely low distortion and accurate amplification. It reproduces the subtle nuances and spatial information of music faithfully, providing a professional-level listening environment.
| Input | RCA x 1, 2.35mm phone jack x 1 |
|---|---|
| Output | Voltage Output / Current Output: 8.35mm Standard Headphone Jack x1 |
| Frequency Response: | 20kHz / -0dB, 100kHz / -0.3dB |
| Current Output Gain (Times): |
Low: 32Ω / 1.3, 100Ω / 3.9, 200Ω / 7.7, 600Ω / 23.2 High: 32Ω / 3.7, 100Ω / 11.3, 200Ω / 22.4, 600Ω / 54 |
| Current Output Input-Equivalent Noise (-dB): |
Low: 32Ω / 89, 100Ω / 98.4, 200Ω / 98.3, 600Ω / 89.4 High: 32Ω / 98.1, 100Ω / 98.2, 200Ω / 95.4, 600Ω / 96.1 |
| Distortion (1 mW): |
Voltage Output: Load impedance = 32Ω / 0.08%, 100Ω / 0.042%, 200Ω / 0.028%, 600Ω / 0.015% Current Output: Load impedance = 32Ω / 0.029%, 100Ω / 0.018%, 200Ω / 0.013%, 600Ω / 0.011% |
| Maximum Output: 1% Distortion Maximum Output (mW) |
32Ω / 14, 100Ω / 42, 200Ω / 82, 600Ω / 37 |
| Gain: | 2-position switchable |
| Power Supply: | 12 AA Batteries |
| Dimensions: | 45mm (H) x 127mm (W) x 170mm (D) |
| Weight: | 450g (without batteries) |
The HDA-5520 MK2 is a headphone amplifier that fully benefits from SCL's proprietary Satri Circuit (SATRI-IC). I felt that the core of its sound lies in its overwhelming sense of speed and clarity. There is extremely little muddiness in the sound, and fine details are conveyed clearly without being buried. Additionally, despite its non-feedback design, it features a very quiet background, with a low noise floor that allows the music signal to emerge in a deep, quiet space. When current-connected (SATRI-LINK) with a compatible DAC or preamp, its potential is further enhanced, expanding dynamic range and significantly increasing the purity of sound. It has delicate expressive power while also driving high-impedance headphones with strength, achieving both smooth mid-highs and tight, powerful lows.
