It's been about 6 months since I conceived the idea.

I've got the device mostly built and wired into breadboard, excepting the LED driver for the arcade buttons, the fader, the piezo and the 3.3v leds.

I've been working mainly on the code and I'm running beta code to load up samples onto the 16Mbyte SPI flash chip and play them back (20 sample polyphony) instead of playing from SDcard (5 sample polyphony).

I have LCD backlight colours and fading implemented which will denote the current operating mode during use.

I modified the standard Teensy PS/2 library to pass through key up and key down information.

I have all the buttons triggering samples through an envelope which gives each sample many more uses; noteOn and noteOff are triggered by the pads being depressed and released. Great fun to play and operates at around 6ms Latency which is plenty good enough for me. Of course, as a sequencer, this will only affect live playing and recording, playback will be in time to the millisecond.

An example of the layout of the audio system is below: