I'm several years away from finishing an EE degree and have yet to get any exposure to DSP. The few texts I've cracked open pre-suppose a level of sophistication i'm not at yet. Is there some stepping stone to start dabbling or is DSP all or nothing?
No, you can start DSP with C, Matlab, or Octave to name just a few. DSP is mainly about filtering, but also about signal processing and algorithms to manipulate sampled signals in the time and frequency domain. A beginner could learn how to implement filters and also spectral estimation. There are also algorithms to detect\generate tones and chords which might be of interest for audio hobbyists. All you need is some sampled data to play with and a way to manipulate that data, the rest is learning about the math (google is your friend).
Real time DSP involves making these processes run fast in an FPGA or DSP processor, which you would need hardware for. I had some labs once where we built adaptive IIR filters that would filter out a tone real time from audio with only a few msecs of delay. We implemented and tested the filters in C and Matlab before implementing them in hardware.
For $60, you can buy a "DM330011-MPLAB Starter Kit for dsPIC DSC" which combines a dsPIC (essentially a PIC24 with added DSP instructions) with a codec..
It is described as:
"This Starter Kit introduces users to the dsPIC Digital Signal Controller device using its speech and audio processing capabilities. The kit is USB-powered, has on-board debug circuitry and 24-bit codec for high-quality audio applications."
ADI ADAU1761 has dual A-D and D-A. with very little DSP knowledge I used it to design and build a mic mixer, controlled by software (i write software). The eval kit is $200. Sigma studio software is easy to learn. tie blocks together like a schematic. EVAL-ADAU1761. I think Audio is a good start. You can generate sine, triangle, square waves manipulate and see on scope or hear on earphones. I am still learning the science under the routines.