Atoll IN50 Signature: Minimalistic integrated amplifier with a classic circuit design

Atoll IN50
Atoll IN50

The Atoll IN50 Signature model has a metal body with an aluminum facade. The developers managed to combine a minimalist design concept with a pleasant appearance. On the left side of the front panel there is a company logo, visually balancing the right side loaded with controls. The central place is occupied by the volume knob, which is attached to the Alps RK-27 potentiometer. On the right is a mini-jack for headphones, a power button with a corresponding indicator, as well as an input selector, which consists of two vertically located keys. Relays are used to switch between sources, and LEDs located in a semicircle indicate which input is currently active.


The Atoll IN50 Signature amplifier has a classic circuit design, where there are no additional circuits, for example, tone control circuits, which contributes to a short signal path. The element base consists of specially selected components, which also include audiophile MKP polypropylene capacitors. The output section contains MOSFET transistors. The model produces 50 W at 8 ohms and 70 W at 4 ohms. Power is provided by a toroidal transformer located on the left side of the housing. The total capacitance of the power supply capacitors is 17874 μF.


The Atoll IN50 Signature has five RCA inputs (including jacks for recording monitoring) and a BY-PASS, which allows you to feed the signal directly to the power amplifier stages. The amplifier also has outputs: RCA for recording, two pairs of preamplifier connectors. Optionally, the Atoll IN50 Signature can integrate a phono stage board. In this case, one of the linear inputs will be activated. The following modules are available for installation: P50 (for MM cartridges) or P100 (for MM/MC cartridges). To connect the acoustics, two pairs of screw terminals are used.


Atoll IN50 Signature has excellent musical talents. The bass is quite articulated, the midrange is well defined, and the high frequencies are open and clear. The model is able to construct a correct three-dimensional scene. The ideal option for working in tandem with the IN50 Signature would be bookshelf speakers that match its class. To obtain more fundamental low frequencies, the amplifier can be connected to small floorstanding speakers.

Atoll IN50 Signature Specifications

Nominal output power 50 W per channel (8 ohms), 70 W (4 ohms)
Pulse output power 90 W
Input sensitivity/input impedance 100 mV / 47 kOhm
Frequency response 5 Hz – 100 kHz
Signal-to-noise ratio 100 dB
Inputs: five RCA; one BY-PASS (RCA) to feed the signal directly to the power amplifier section
3.5 mm outputs for headphones, RCA for recording, two preamplifier outputs PRE OUT (RCA)
Phono stage is available as an option, proprietary P50 modules can be used for installation inside the amplifier (for MM-cartridges) or P100 (for MM/MC-cartridges)*
Power supply toroidal transformer with a power of 170 VA, total capacity of buffer capacitors – 17,874 uF
Output to speaker systems 2 pairs of gold-plated screw terminals
Dimensions (WxHxD) 440x90x300 mm
Weight 7 kg

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