ESX QS-FOUR

Following the great success of the sensationally small 2-channel power amplifier QS-TWO (just 90 x 35 x 70 mm), ESX set itself the goal of developing an equally small but powerful 4-channel version. With the brand-new QS-FOUR, this ambition is now a reality: The ultra-compact 4-channel power amplifier is now available – and is only 10 mm wider than the 2-channel model. With an impressive 4 x 60 watts RMS in just 90 x 35 x 80 mm, it sets new standards in the field of nano amplifiers.

Many people wonder: Why so small? The answer is simple: Mini power amplifiers can be installed directly in the dashboard as plug-and-play ISO variants. Simply connect the cables – and the front and rear speakers are powered, including the power connection. The special thing: In vehicles with an ISO connection, everything is already prepared, so that no additional power cable needs to be laid. The QS-FOUR is perfectly suited for this. Thanks to its impressive efficiency of up to 90%, it also only requires 5 to 10 amperes of continuous current when listening to music – a performance that the factory power cables can easily handle.

Should the desire for more bass arise, that is no problem either: The QS-FOUR has special low-level outputs with which active subwoofers such as Q168A, Q201A or HZ800A can be driven. These outputs can also power larger mono blocks such as QL500.1 or QL750.1, which come into question if you want to install separate subwoofers.

Once connected, the  QS-FOUR will amaze you. Because in most cases, the factory speakers are significantly better than you think. Often it is due to the installed radios, which simply deliver too little power. If you want to listen to louder music, the speakers "scratch". If you then think that it is the speakers' fault, you are wrong. Because the so-called "scratching" usually comes from the amplifier built into the radio, which is at its limit.

In this full-load operation, the amplifier distorts. This is known as "clipping". An additional amplifier always solves this problem. However, these are usually very large and must additionally be connected to the battery with thumb-thick power cables. ESX developed the QS-FOUR precisely for this purpose, which delivers 4 to 6 times as much power as conventional radio amplifiers with up to 4 x 60 watts RMS. And that with very low power consumption, the lowest distortion factor, and in state-of-the-art Class D technology.

The nano amplifier is also available as an ISO variant.