the terretron_505




here's a project i've been working on for a while now, a circuit bent roland tr-505.
as many of you probably know, the 505 is the runt of the x0x litter.  so what do you do
with a piece of crap drum machine, six pounds of various switches and jacks, a chunk
of scrap aluminum from your way-cool dad, and three feet of poplar? you trick that bitch out!

the layout




patch matrix

the whole design is based around the patch matrix. the 30 patch points connect to 
various points within the 505, mostly on the main sound chip (thanks to the burnkit2600
crew for the tips). this works like a regular patch bay, connecting each point to any other
point via rca cord.

point-to-point enablers

the point-to-point enablers give the user the option to put a switch between any two
patch points.  you then have a choice of on/off toggle or momentary pushbutton to
enable the patch.  the pushbuttons are made by alcoswitch, they are really
high-quality parts and came with those sexy finishing nuts.

multiplexing busses

the multiplexing busses allow the connection of two or more patch points and and are 
also switch enabled (via 4PST toggles).  the buss combiners allow the
multiplexing busses to be joined together for a total of 16 multiplexed points if you really 
feel like bringing the poor bastard to his knees.  unfortunately, without a more complex 
switching network you're only able to join the busses to adjacent busses (i.e. 1-2 or 3-4, but
not 1-3 or 2-4 etc).

distortion select

this is a rotary switch that enables any one of six distortion flavors at a time.  the toggle
 switch allows you to flip it on/off on the fly.

sounds

coming soon

final thoughts

between the wiring, woodworking and metal work, this project took me several weeks to finish.  
i wasn't working on it full-time mind you, i would estimate about twenty hours total build time.
i have to thank again burnkit2600 for the bend tips.  i also need to thank my dad for hooking
me up with the aluminum for the panel, as well as letting me pick his brain and letting me
use his shop for the wood/metal work.  i'll clean it up next time i'm over dad :-]

more pics (click to enlarge)