Specialized in the design and manufacture of high-end loudspeakers and speakers, Atohm® also designs and offers amplifier modules with a very high level of performance. Thanks to their sophisticated signal processing, Atohm® modules offer a wide range of settings and connections to meet the most demanding applications, such as active subwoofers in closed or bass-reflex loads, active loudspeakers or single-ended power supplies. All this while offering excellent technical performance and great musicality in a very small footprint.

Extensive research has been conducted by the brand on components, schematics, layout topology, power supply and overall construction to develop the best products.

The Atohm® S250-MK2-X amplifier module includes many features and specifications:

• Ice Power™ output stage rated at 220W RMS into 4Ω. Class D technology, providing excellent 80% efficiency and a high damping factor, making the module compatible with any load impedance greater than or equal to 3Ω. Great musicality and generous power in a very small footprint.
• The X-GUARD™ technology bypasses the disadvantages of a classic subsonic filter by ensuring that the loudspeaker's excursion never exceeds an absolute limit (risk of breakage, very high distortion) whatever the amplitude of the input signal. This technology preserves the signal and its phase (unlike a subsonic filter). The extreme bass is more faithful, the connection with the main speakers more homogeneous and the loudspeaker protected. The S250-MK2-X offers 6 internal settings (X25, X30 and X35) and (AMPLITUDE1 / AMPLITUDE2) via jumpers. The activation of this function is done via two settings available on the front panel: X-GUARD1™ and X-GUARD2™.
• In addition to a classic linear mode, the S250 module has two "CLOSED" modes designed to extend the response to very low frequencies of the speaker(s) mounted in a closed load. This is not a simple boost but a transform equalisation. The choice of mode 1 or 2 is made by internal adjustment. The activation of the "CLOSED" mode is done via a setting on the front panel.
• The U-GUARD™ device reduces the formation of square wave signals at the output of the device and prevents saturation of the power stages. Thus, whenever the signal exceeds the defined threshold, the U-GUARD technology limits the formation of harmonics. This is an essential function, especially when using a subwoofer, as harmonics can make the subwoofer perfectly locatable. It also allows to maintain a signal shape closer to the original one.
• Module totally assembled in France.

The module can be connected via the pre-out / subwoofer output of a preamplifier / processor or directly to the speaker outputs (in parallel) of a conventional stereo amplifier. The S250-MK2-X module can also be bypassed for high performance HiFi broadband use (mono block) via a simple internal modification. In this case, only the gain control remains active. This can be used for the realisation of monitoring loudspeakers, for example.