Digitally Controlled Audio Power Amplifier with Virtual Surround Sound

In this post we describe digitally controlled 2.1 channel audio power amplifier with virtual surround sound. This audio amplifier is based around Microchip’s PIC18F452 microcontroller and ST microelectronics TDA2050 power amplifiers.


Key system specifications and features of this audio system are listed in below:

• Supply voltage and PSU: D.C - 16V to 19.5V with 3A PSU. (Recommended: 18.8V, 3A PSU)
• Input(s): 2 analog input lines. (for Left and Right channels)
• Functions: Volume, Bass, Treble, Loudness, Mega Bass, Surround Effects
• Volume control: 0dB to 75dB Attenuation per channel with 1.25dB step
• Mute: 100dB Attenuation per channel
• Calculated channel separation (Approximately): 85dB - 88dB
• Bass control: ±14dB with 2dB step
• Mega bass control: 0dB to 30dB with 7 control steps
• Treble control: ±14dB with 2dB step
• Surround Sound: Based on AViSS 3D surround algorithm with 4 operational modes (Disable, Low, Normal and Wide)
• Output channels: 3 (2 channels + 1 subwoofer driver channel)
• Output power: 20W (PMPO) in 8Ω load
• Output power of subwoofer channel: 20W (PMPO) in 8Ω load
• Recommend speaker configuration: 2 × 30W 8Ω full range speaker(s) for 2 output channels. 1 × 4Ω 50W woofer for "subwoofer driver channel".
• Control interface: IR remote control with SIRC protocol

Other than above features this system equipped with digital UV meter (for both the input channels) and complete menu system.