Wizz : The Engineer

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The UberMixer is inspired from the Aurora Mixer 224. I've been thinking for some time to create a custom mixer/controller for Ableton Live, but I've recently bought Traktor Scractch Duo and it's the perfect time to create a mixer/controller for Traktor.

In brief, the UberMixer is running a ATmega164P at 20 MHz with a 16 channel analog multiplexer. A FTDI USB chip provides the interface to the computer using a MiniUSB connector. The device is bus-powered and will appear like a MIDI controller to the computer. The user is provided with a 3 band EQ (Hi/Mid/Lo), gain, Filter with on/off, track volume, 4 loops + out for each track, cue prelisten, along with monitor and master volume. Traktor will also feed back the dB values for each track, which will be displayed on the VU meters.

The UberMixer CAD

Using CAD as always to see if everything fits

The mixer is now mostly complete, I simply need to fabricate the metal casing and it's done. The PCB has only 2 errors (dumb errors if you ask me...): I inverted the RX and TX line for the FTDI chip, and I inverted the reset and latch lines for the 7HC595 chips... two stupid errors that I already had on previous designs, but sometimes you think it's right but it's not. I must admit the SCL and RCK notations for the reset and latch lines of the shift registers aren't very clear, it's easy to get confused with these. For the FTDI chip, I was thinking like a MAX232 converter where you connect the RX line to the RXin pin, but the RX/TX notations on the FT232RL are from the computer's point of view.

Bottom line is : double check EVERY f*ing thing on your CAD software before production. Even stuff that looks obvious.

The UberMixer CAD

Just need a box to fit everything in

© Charles Gervais-Dumont 2013