Precision Headphone Amplifier

Small, compact and robust, the Bacillus is a precision grade headphone amplifier that comfortably adapts to any impedance headphones. The bright profile is quick in transitions and urges a direct sound, most notably in rock genres. But the low distortion also adapts quickly to acoustic and delivers a very realistic and intimate experience. All in all, Bacillus is an impressive performer and thanks to its diminutive size is an ideal road companion for travelling sound professionals. The Bacillus might be our entry-level headphone amplifier, but on looks and performance you could be forgiven for thinking this elegant headphone amp is among our high-end range – it’s only our generous price tag that gives the game away.

Microaccurate headphone amplifier
499 EUR

Headphone amplifier isolated on a white background

Technical Specifications

Headphone impedance: 8-600 ohm

Output power: 181.5 mW (8 ohm)/161 mW (600 ohm) 

Frequency response: 3 Hz-500 kHz, -1dB 

THD (1 kHz): 0.0003 % 

IMD: 0.025 % 

Power consumption: > 3 W 

SNR: >102 dB 

Power supply input voltage: 230 V/50 Hz or 115 V/60 Hz 

Dimensions (W x H x D): 110 mm x 64 mm x 180 mm 

Weight: 850 g 

Character: Slightly bright


5 years warranty

class AB final stage 

Wima quality pulse input capacitors 

audiophile grade op-amps 

double 180 MHz/250 mA Burr-Brown current buffer 

Alps Blue Velvet volume potentiometer 

no output capacitors 

gold plated RCA connectors 

silver plated interconnecting wire on input 

on-board 2 x 15 V stabilized power supply

Bacillus' Story

The Bacillus was the first project we successfully completed - although it wasn't the first we started. The initial prototype looked pretty cute: small, compact, stylish and finished off with a shiny acrylic front panel.

Our intention was to create a portable headphone amp that was as small as possible. Initially, the chassis on the Bacillus was 5 mm shorter, but because of the crowded rear we felt it was too risky so opened her up a little.

Fortunately, we were able to maintain a compact size which is quite a feat when you consider the amp has a built-in power supply, huge input capacitors and a heat sink. And because of its size, we wanted to name it after something small – and bacteria (lat. Bacillus) seemed appropriate. 


  • Review by, Romania (in English)
  • Review by, Poland (in English)
  • Review by HiFi Wigwam, UK (in English)
  • Review by Old & New Sound, Spain (in Spanish) 

  • Thoughts

    "The way in which the colors, the location of instruments, their intensity and even the recording temperature are differentiated is definitely way beyond this particular price level, it's simply unique."
    Wojciech Pacuła,

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