Hey All,
After extensive research, talking to engineering nerd friends, and general hair-pulling, I'm here for advice.
My project is a standalone, 8-channel (octophonic) sound source; audio read from files stored internally or read off a disk.
Signal path is: WAV from flash memory->8-channel DAC->8 channels of amplification->speakers
Essentially, user presses a button to play, and controls gain of four stereo pairs that play in sync.
I have seen an 8-channel player on the market, used mainly for art installations, that looks just like what I'm trying to do in terms of DAC. It's called a Waveplayer8: http://www.waveplayer-systems.com/
I'm guessing the quality with that isn't great, but the quality for this project doesn't have to be, either. I'm fine with 16-bit sound. While I could just try to track one down, I'd much prefer making something more customized and understanding the signal flow.
I'm guessing there are projects like this out there, but I've been unable to find them.
Starting really small, with about 3w per channel, I'm looking at something like this:
For context, this is my first time building anything more complicated than a condenser mic. Any advice would be very much appreciated, large or small.
After extensive research, talking to engineering nerd friends, and general hair-pulling, I'm here for advice.
My project is a standalone, 8-channel (octophonic) sound source; audio read from files stored internally or read off a disk.
Signal path is: WAV from flash memory->8-channel DAC->8 channels of amplification->speakers
Essentially, user presses a button to play, and controls gain of four stereo pairs that play in sync.
I have seen an 8-channel player on the market, used mainly for art installations, that looks just like what I'm trying to do in terms of DAC. It's called a Waveplayer8: http://www.waveplayer-systems.com/
I'm guessing the quality with that isn't great, but the quality for this project doesn't have to be, either. I'm fine with 16-bit sound. While I could just try to track one down, I'd much prefer making something more customized and understanding the signal flow.
I'm guessing there are projects like this out there, but I've been unable to find them.
Starting really small, with about 3w per channel, I'm looking at something like this:
- Power supply:
- AC-to-DC power supply
- Voltage regulator
- Microcontroller:
- ADAU1452 digital signal processor with integrated sigma-delta DACs (one per channel)
- Crystal oscillator for generating the master clock signal for the DSP
- I2C interface for communication with external devices, such as an SD card reader
- Memory storage:
- SD card slot for storing the 8-channel sound file
- Voltage level shifter to convert the 3.3V I/O signals of the SD card to the 5V logic level of the ADAU1452
- Pull-up resistors for the I2C interface
- Audio output:
- 8 output buffers with a gain of 1 (one per channel)
- Output coupling capacitors to remove DC offset from the signal
- Output connectors to connect the analog signals to the amplifiers/speakers
For context, this is my first time building anything more complicated than a condenser mic. Any advice would be very much appreciated, large or small.