audio dsp preamplifier

audio preamplifier-FIR crossover. 3 analog stereo inputs, 2 optical and 2 coaxial digital inputs , 8 analog outputs and 1 coax output. everything controlled using pic microcontroller, lcd, rotary encoder. For volume i use the cs3318 analog digitally controlled ic. for dac i use the PCM1794a ic's and for ADC the cs5361. as digital receiver the cs8416. all the inputs are delivered to the minisharc dsp. the outputs from the minisharc (i2s) goes to the pcm1794a. the dac analog output goes to the volume control chip and the via opamp buffers to the output connectors. the project as you can see is not completed yet.

Step 1: audio dsp preamplifier

four layers blue gold plated pcb board for my new preamplifier. board size is 130x232mm. it is not completed yet as you can see on the photos. there are 3 analog inputs which are selected via relays and goes to the ADC. The adc outputs the digital signal in i2s format.

The digital inputs goes to the digital receiver ic which outputs the signal in i2s format too.

i have one isolated auxiliary input (i2s)

those 3 i2s signals goes to the input selection ic's which are controlled with the pic microcontroller (the digital receiver is also communicating with the pic for input selection.

then the i2s output from the input selectror circuit goes to the minidsp minisharc processor.

the outputs from this processor goes to the clock buffer/drivers ic's and then to the four dac ic's (pcm1794a)

from those dacs the analog outputs goes to the cs3318 analog volume chip which is controlled with the pic microcontroller also. the via a output buffer goes to the output connectors.

all the functions can be controlled via remote control also and are displayed on led display.