DTMF 16 Channel sequencer

I had some success today with breadboarding a DTMF based 16 channel audio sequencer. Thanks to John Schuch for the original idea and for drawing up the schematic. The basic idea is to be able to route an audio signal to any 1 of 16 speakers. You control it by feeding it stereo audio - in the left channel, you have the DTMF tone corresponding with the number of the speaker you want the sound to come out of, and in the right channel, you simply have the sound itself.

At this stage, I am using 8 LEDs, instead of 16 relays, LEDs because the relays I have don't line up nicely with the breadboard, and only 8 because I am lazy. You can see them blinking away in an entirely unexciting fashion in the video below. While not being very exciting, those LEDs lighting up certainly gave me a sense of accomplishment.