What is Digital Signal Processing and what can I use it for?
Well I am not going to cover this in detail here, it would take a long time. There is a lot of information on the internet for the uninitiated.
Simply you are manipulating data in the digital domain, this data is normally a representation of some form of analogue signal. Whilst most analogue signals can be manipulated in hardware (op-amp filters, amplifiers etc) converting these signals into digital form allows for a much greater range of functions to be performed, generally at much lower cost, than would otherwise be possible.
Here digital signal processing is taken as the manipulation of audio signals in the digital domain. These signals can originate and be sent to any analogue or digital source/sink with the right hardware. This platform is designed to allow any interface (analogue or digital) to be added by simply designing and adding on the right interface hardware, whilst maintaining a constant core system.
So what is this DSP Platform?
This DSP platform is a selection of inputs (analogue/digital), a digital signal processor, and a selection of outputs (analogue/digital). All of these functions are performed from interconnected small boards you choose based on what you need.
What is the "core hardware" to make a working DSP System?
The Analog Devices SigmaDSP ADAU145x DSP board can work on it's own, however you do need an EVAL-ADUSB2EBZ USB to I2C/SPI adapter or equivalent device for programming from SigmaStudio. If fitted with an ADAU1451 or ADAU1452 chip these have SPDIF input and output, but the ADAU1966 DAC board will give you up to 16 channels of analogue outputs to play with from a SPDIF source.
ADAU145x SigmaDSP devices use the closed-source SigmaStudio software. Eventually I would like offer open source development tools and software based on the CoreOne design. However SigmaStudio is very easy to use and is a free download.
Where did this all come from?
This idea started after buying an AV amplifier which was outdated by a WiFi/network model almost immediatly. My idea was a audio/video platform that you could upgrade as technology changes or if you just need something different. With the throw away society we live in it didn't seem viable. AV equipment just gets better and cheaper.
A while later I was looking around for a DSP platform to use as digital crossovers. I almost went with a project Elektor published but the MiniDSP 2x4 boxes worked out similar cost and are very easy to use. There wasn't much other choice, even the expensive options looked limited. I wanted something better, lower noise floor, more flexible DSP processing. I realised I could design and build a much more flexible system myself from scratch for a reasonable cost.
They where almost the same project, but my new idea has much greater flexibility because of some small changes. For me this project came with minimum risk and seemed like a fun idea that other people might be interested in; hence putting this site up. All boards I am desiging do things I want to do; but that doesn't need to be the limit of this project, always open to good ideas!.
How much effort and money is all this?
Well this depends how much effort you put in. I am not doing this to become rich but if I ever sell boards they would not be that cheap. This project is not like a SBC, it's also not "plug and play" and you need some electronics and computer skills.
As I am not selling boards you need to make these yourself. But SMD soldering is not that hard and PCB costs these days are low from places such as DirtyPCB. I have kept parts larger where possible at the expense of not fitting as much on a PCB. There are some 0603 capacitors and resistors where I needed them but most are bigger. Some ICs are tricky but solder wick helps!