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Category Archives: keyboards

ok back again…

casio pt-1

this is the 2nd CASIO keyboard I circuit bent…as usual the controls are placed on a extension unit through a serial cable because of the small space left inside the keyboard case…the box was a speaker from Virreina church in Gracia…(found beside it)

again no diagrams yet until I am back on my workshop in Barcelona… anyway if i’m not wrong, there was not many interesting glitch points on the board but the ones coming from the big chip in the left side… as soon as i get my hands on my notes i will update this post with a couple diagrams…

what does what

like in the other keyboard (PT-87) i tried to find alterations for the on board rhythms section, kind of low-pass filter and high pass filter, some distortions, and two interesting bass-lines heartbeat like that can be controlled with pots… On the other side, the pitch resistor was substituted by a long fader with a higher value than the original on board little pot which takes the rhythm tempo and pitch to an extremely slow speed, turning hit hats and drums in to beautiful noisy crash sounds, three body contact points were also added to achieve a more natural hands on way of playing, some of this points were duplicated to give more resolution to the effect…

body contacts

and finally a reset button (disconecting batteries) for when things go really wrong, (if it can be considered wrong when the little beast takes control of it’s own grunts…

and here a video:

another hack by 9volts

update: i found some pics of the circuit board with some bend points soldered ; don’t remember right now what does what as i said i will update later here is the pic:

some interesting points on PT-1 circuit board


This was actually my first succesful bent circuit, before that i burnt a couple toys on the process of bending (never knowing when to stop i guess).

bent PT-87

i don’t have at the moment my notes and diagrams to share (i’m on my annual missouri vacations), but i will defentley update this post in the future with them when i’m back on the base in Bcn…

what does what

and here is a video: