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Roland TR-505

Roland TR-505 Service & Owner’s Manuals

June 10th, 2010 by gumi | 2 Comments

Roland TR-505 Service & Owner’s Manuals

Download the Roland TR-505 Service Manual Download the Roland TR-505 Owner’s Manual


Roland TR-505 IC1 “Sequencer Glitch” Bends

June 8th, 2010 by gumi | No Comments

Roland TR-505 IC1 “Sequencer Glitch” Bends

We benders owe much to squidfanny for having the nards to bend IC1 (which resulted in possibly the raddest bend on the TR-505 ever) and for sharing what he learned. I hope to clear up any confusion over how to bend IC1 here. In my opinion, this is a “must bend” for anyone tinkering with […]


Roland TR-505 Audio Demos

June 7th, 2010 by gumi | No Comments

Roland TR-505 Audio Demos

Here are a few recordings of the Gumi modified Roland TR-505. Each track used IC1, IC11, and R39 exclusively. The pitch modulation is handled by IC1, which drives an LED at different rates. The LED shines onto a CDS cell, which then changes the resistance at R39 as it flashes. “Synthefive” features the synth tones […]