This was my first 'serious' home made amplifier, that I built in 2001. The pictures are from 2002/2003 when I got my first digital camera. Prior to that, my adventures were only in small amplifiers of no more than 3W. This amplifier features surround sound and is an entirely analogue construction.

Features:

• 20W per channel RMS power to front left and right channels via TDA2040
• 20W RMS power to both rear channels via a single TDA2040 (speakers wired in parallel)
• 14W RMS power to centre channel via a single TDA2030
• Pre-amp with loudness filter and tone controls
• Hafler Matrix surround sound decoder with centre channel output
• Level controls for front, rear and centre channels
• Power switches for rear and centre channel amplifiers
• Headphone output and switch
• Inputs for external decoders (i.e. 5.1 Dolby® Surround Sound)
• Centre and Subwoofer pre-outs
• Temperature Controlled cooling Fan
• Power supply from an 80VA 12V AC transformer

It was my first big build and I had lots of fun building it. Whilst I look now at some horror, it was a real sense of achievement for me to make something quite complex, having never studied electronics, and it set me up for a path of building more electronic projects. Not only did it work, it packs plenty of punch for 20 watts per channel and actually even sounded pretty good :-)

http://sound-au.com for most circuits was used for the resource for most circuits, including the PSU, the preamp, tone controls, surround sound processor, and temperature controlled fan. The rest of the circuits came out of the datasheets for the TDA2040 and TDA2030 chips.

For those who want more information, I did make a manual for it too. I think I got bored, and wanted to try out the newly obtained Word 2003!

Below are some pictures of the amplifier and were it was configured in my room of my parents' house, my first university room, and testing with Dad's speakers. Pardon the quality, the camera was only 2 megapixels and I was a novice back then!

View of amplifier, cover on

View of amplifier top, cover off

View of amplifier front, cover off

View of amplifier back, cover off

Amplifier under testing with mp3s playing from a laptop

Amplifier setup in my university room

Closer view of amplifier setup in university room

Amplifier setup in my room back when I lived with parents