IN50 Signature

The integrated amp-preamp IN50 Signature is manufactured with the greatest care: we choose the best possible components to achieve the highest level of sound performance. This rigorous search for perfection goes through the design of proprietary ATOLL circuits in order to preserve the integrity of the most subtle musical signals.

  • 4 mm brushed aluminium front panel.
  • 2×50 Wrms / 8Ω.
  • Toroidal transformer of 170 VA.
  • ALPS motorized potentiometer.
  • Filter capacitors: 2×6800 μF.
  • Single push-pull MOS-FET power stage.
  • Monitoring loop.
  • Discrete component audio stages.
  • MKP Technology Link Capacitors.
  • High-performance heat sinks, direct thermal coupling.
  • Double-sided circuit boards with nickel/gold finish.
  • Polarization of output stages in class A/B.
  • Thermal protection.
  • Optional DAC board: DA100 or DA200.
  • Optional PHONO board: P50 or P100, can be combined with the DAC board.
  • Optional ATOLL global remote control.


5 Audio inputs (RCA): AUX (or optional P50 / P100 phono stage), CD, TUNER, DVD, TAPE (IN + OUT).
1 BY-PASS input (used as a power amplifier).

2 Line preamp outputs (for bi-amplification or to connect a subwoofer).
1 Trigger output (12V).

1 Headphone jack Ø 6,35 mm.

Our balanced MOS-FET amplifier circuits offer excellent harmonic gradients and have no memory effect, every moment, the current is immediately delivered to your speakers. This is one of the secrets of the musicality that ATOLL amplifiers enjoy.


Output power Wrms/8Ω: 2×50 W
Output power Wrms/4Ω: 2×70 W
Power supply: 170 VA
Total of capacitors: 17 874 µF
Number of inputs: 5+1 BY-PASS
Preamp outputs: 2
Bandwidth: 5 Hz – 100 kHz
Rising time: 2,5 µs
Input impedance: 357 kΩ
Sensitivity: 100 mV
Signal/Noise ratio: 100 dBA
Distortion rate at 1 kHz: 0,05% / 10 W
Dimensions: 440×305×95 mm
Weight: 7 Kg


1 Phono board on the AUX input (optional):

  • P100 (configurable MM or MC).
  • P50 (MM).


1 Digital board (of your choice):

  • DA200
    2 Coaxial inputs (24 bits/192 kHz).
    2 Optical inputs (24 bits/192 kHz).
    1 Bluetooth receiver.
    1 USB-B input: PCM & DSD.

  • DA100
    2 Coaxial inputs (24 bits/192 kHz).
    2 Optical inputs (24 bits/192 kHz).


Important: Using the USB input of the optional DAC board requires downloading a specific driver for Windows computers. This can be downloaded below. This driver is not necessary under MAC and Linux.

Download it here:


Optional remote control (allowing control of all products: Integrated, CD Players, Tuner, DAC).

“As good wine gets better with age, the IN50 Signature represents the culmination of over 25 years of research, testing and refinement of a now proven scheme. Certainly intended to be accessible to the greatest number, this device is nonetheless endowed with an ultimately quite aristocratic character. In no case will we discuss its positioning here without legitimately asking the question of whether it does not simply represent the beginning of the top-of-the-range?”

Laurent Thorin, Vumetre magazine, No. 33, January-February 2021

The IN50 Signature is available in black or natural aluminium version:

L'amplificateur intégré IN50 Signature est fabriqué avec la plus grande des attentions.
Black anodized brushed aluminum finish.
Silver anodized brushed aluminum finish.