The Aitos EV 803 Mono Output Transformer Less Power Amplifier (OTL) is a no-compromise 90 watt OTL mono power amplifier. After the success of the EV801, continued research combined with customer and listening panel feedback resulted in the production of the EV802 followed by the current model the EV803. Each of aims The EV802 mono amplifier has a music power rating of 90 watts into 8 Ω. The EV 803 is powerful enough for most popular speakers, but is an especially good match for e.g. the Quad or Martin Logan electrostatics. The EV802 model introduced a number of changes like a closed chassis housing to comply with EU legislation, circuit upgrades and a soft start to the filament and high voltage feeds to prolong tube and component life. 

The current model, the EV 803 has a larger power supply with lower internal impedance and improved electrolytic capacitors. This resulted into an even higher resolution and ultimately in a more life-like performance.