I love this, it's a great hack. It seems like the real sweet spot for a project like this though would be to capture the AirPlay audio at a line level and patch it into existing speakers and power amplification circuit. That way you could capture the existing audio quality of a device that had good sound reproduction but is otherwise obsolete. Was such an approach considered?
Considered yes, but I'm coming from computer science, not electronics so I just didn't know what all the parts are doing and it will take time before I learn about it. I'm eager to learn it but it is quite complex and a lot of work which would get in the way of finishing the project within a short time frame. The next time I will go one step further, I promise :)
Mine's a Doctor Who's Tardis + Pi running Mopidy (raspbian + some packages for playing music from multiple services, airplay support and remote control with a webapp). Making the thing was totally worth the cost :)
If & when you get time, I for one would be very interested to read the blog post! Even just a list of the packages you used (with the airplay support + associated webapps) would be handy!
I've just set mine up for timelapses at the moment. Nothing fancy, but it does make for pretty videos every day :) https://www.youtube.com/watch?v=rVxBJN5Pd_E (since this one, have worked out how to turn the LED off, and I don't take it through the night any more).
Yip, once a minute between sunrise and sunset (now) and then run a little script to turn it into a video, and then use a nice little cli (googlecl) to upload it to youtube (though that has been slightly tempermental). It's really really straightforward.
I'm about to do something similar except I'm using an old AM Test Transmitter from the 50's as the chassis http://imgur.com/a/FtamZ (thing has valves and still works!).
It has enough space to put in a pi,dac,amp into the middle box in the second picture (which is perfectly centred) then I'm going to build some mdf cabinets and put the speakers either side (with lots of dampening).
Going to keep (and make work) all the front switches, power output (top right rectangle) is going to be replaced with a backlit LCD display and the tuning dial (main face) is going to be kept but backlit with LED's that change color to indicate station/volume.
On the back, audio output (in case I want to use external speakers) plus HDMI and USB connections (so I can plug a monitor and keyboard in to do config without disassembly).
Case had so much internal space I was tempted to put a media PC in it but I have one already and a radio seems fitting somehow.
I'm doing a similar "fun" project this weekend (for some definition of fun) - wiring up an rPi to a 1982 ADDS Regent TTY @ 9600bps. The Pi is installed internally with wifi and takes power from the terminal; all the other connections are internal to the terminal. So, plop it down in any room, turn it on, and have a fun conversation piece / something to play nethack on.
There is a critical mass issue with things like this in needing to have several of the microcontroller devices available, so you don't feel bad about "burning" on by actually embedding it in a project.
Does it play audio perfectly in sync between the two devices and if so can u easily add/create additional speakers? Fill your house with audio on the cheap?
No, it works like the AirPort Express, it buffers a couple of seconds (perhaps 5 or something) and first then plays it. This is build in into the AirPlay protocol to prevent gaps in the audio.
