Tuesday, June 29, 2010

TR 505 XL

This is what happens when you give me a TR 505.
The 505 is a digital drummachine made by Roland. It has a nice, easy-to-use sequencer, a big display, full MIDI capabilities and some of the most boring sounds that you'll ever hear...
Time to mod it, I'd say!
It now sports single outputs (1/4") and trigger outs (1/8"). Especially the trigger outputs are quite handy for owners of a modular synth... the 505 will work as a MIDI-to-trigger converter too!
Also the sounds are now tunable - I added 8 new oscillators (this time 40106 based, unlike the 555 based ones on my TR 707) to accomplish this.
I also added volume controls, so now there are 16 new knobs on the front panel. The volume controls are doubling as a"crunch" control, which goes like this: the maximum volume is reached at the 12 o´clock position (and the potentiometers have a center detent to reflect this), turning the knob further to the right will overdrive the internal mixer stage a bit, resulting in a slightly distorted sound. This adds a nice punch and grit! Due to the way the mixer stage is designed this will only work on the main outputs.
Most of the necessary informationon how to do these mods can be had from the Burnkit2600 TR505 page, so thanks to those guys!
All that stuff did not fit into the stock enclosure, I had to make some side cheeks out of stained plywood in order to raise the height of the case by 3cm.

Check the sound sample below for a glimpse of what this machine sounds like. No FX, no overdubs, no EQ used - recorded straight from the master output.


ji said...

great work! =)

Anonymous said...

one of the better 'bending' efforts I've seen but I have to agree with others... What you have done could have been achieved really easily as a small electronics project. Let's keep the old machines for posterity. They're getting on a bit now :)

_UNKN said...


collin crowe said...

i tried the trigger outputs on my tr505 based on what's been put online, but i don't think they have enough juice to hit the 5 volts needed to trigger a moog or a juno or anything. did you have to add transistors? any help would be appreciated

RaffaJaffa said...

i also would like some help. Is it possible to get any more detailed info how to add 8 new oscillators this time 40106 ...