While the Facmogu F900 Mini Bluetooth Power Amplifier is the smallest mini amplifier on our list, it measures 3 x 2.7 x 1.5 inches, which is incredibly tiny. However, one of the smallest mini amps on the market, the NS-10G Bluetooth 5.0 2 Channel Power Amplifier just beats it by measuring in at a super-compact 3.15 × 2.09 × 0.87 inches.