The Fosi Audio E10 is a Class D amplifier that is both powerful, efficient and affordable. It embeds a TPA3251D2 amplifier chip allowing it to develop a comfortable power of 2*125W under 4Ω with a high efficiency, a low distortion and a wide dynamic range, for a sound restitution as precise as musical. Moreover, the E10 offers a complete range of connectors allowing it to adapt to most of the use scenarios. We find stereo RCA, Toslink optical, coaxial and a USB-A port for storage device, completed by a Bluetooth 5.0 reception capacity. Practical, the latter offers the possibility of broadcasting and controlling its music remotely easily from a smartphone or a tablet for example. On the output side, the amplifier offers of course speaker terminals but also a pre-out RCA output that can be used as a subwoofer output.