Amp Box S3 offers one stereo RCA input and delivers powerful, room-filling sound through your speakers. The sophisticated PCB concept & circuit topology achieve less distortion and a better signal-to-noise ratio than its predecessor. Voiced to approach the sonic characteristics of tube amps, Amp Box S3 sounds rich & musical and it highlights the warmth we love about analog. Due to its relatively tiny footprint, it is also the perfect solution where space is a factor. For example, it’s a great fit for desktop nearfield monitor speakers and for any system that requires top-notch performance in a small package.

Technical Improvements Over Amp Box S2

• The class-D amplifier for Amp Box S2 was built based on the Renesas R2A15108SP chip while
Amp Box S3 is based on the TPA3221 chip, which provides better audio parameters (efficiency
• The PCB in Amp Box S2 was 2-layer while the PCB in the Amp Box S3 is 4-layer; a precise PCB design
with an emphasis on improving audio performance (crosstalk, THD+N, SNR) and EMC parameters.
• Amp Box S3 has improved voltage filtering from the power adapter.
• Amp Box S3 has improved cooling for the class-D amplifier; a single-cast aluminum profile with greater heat transfer.
• Amp Box S3 has better frequency transmission at 20kHz by 1.2dB.
• THD+N is about 10x better in Amp Box S3 than in Amp Box S2.

Additional information
Weight 0.385 kg
Dimensions 11.8 × 10.3 × 3.6 cm



  • Latest PCB concept & sophisticated topology
  • Lower distortion & better SNR than S2
  • Ultra compact with audiophile sonics
  • Advanced amplifier module
  • Metal enclosure isolates from vibration and interference
  • Made in Europe


  • Power output: 2 x 23W (4 ohms), 2 x 40W (8 ohms)
  • Peak power: 2 x 50W (4 ohms)
  • Frequency response: 20Hz-20kHz (-0.7dB @ 4 ohms)
  • Channel separation: > -68dB @ 20kHz
  • Signal-to-noise ratio: 87dBV (100dBV, ‘A’ weighted) @ 4ohms
  • THD: <0.02% @ 10W, 4 ohms
  • Gain: 31dB
  • Input: 1 pair RCA sockets
  • Input impedance: 25k ohms
  • Speaker sockets: 4mm Ø bananas, spades, pins or bare wire
  • Trigger 12V DC: in/out, 2-pole jack, Ø 2.5mm
  • Power supply: 20V/3A DC (universal power supply)
  • Dimensions (WxHxD): 103 x 36 x 118mm
  • Dimensions (standard): 4.06 x 1.42 x 4.65″
  • Weight: 385g (0.85 lbs) without power supply