DIY Home Theater Preamplifier

Designing a very own home theater system is the main goal of this project where a 7.1 preamplifier was desired to be constructed.

The preamplifier contains three analog inputs chosen by relay input selector that includes Tuner, DVD, and AV. The USB input is on PCM2702 and there is an input for additional 6 home theater channels. Also available is a built-in analog 7.1 surround matrix using OPA4134 along with 7.1 analog output. On the TPA6120 is the headphone output the external device can be controlled by four trigger outputs and all available functions are control by simple remote. The firmware upgrade uses SIP programmer input.

For manual operations, all the control is provided by 7 pushbutton switches consisting of the Power, Mute, Mode, OK, -, +, and Input. The display shows the selected input and volume level when switching ON. The information whether the preamplifier is connected or disconnected to other USB device is shown when USB input is selected.

The actual sampling rate or unlocked when unable to lock SPDIF are shown on digital input. If set, there will be Mute sign on mute condition and time remaining to switch OFF.

Click here to see the rest of the project.