CIRCUITBENDING

Im starting with some of my previous experiences of sound art, namely circuit bending and diy electronics.

Above is the "speak and spell" manufactured by texas instruments in the 60s. this toy was popular with children and teachers as it was a cheap and effective way to tweach spelling and to increase vocabulary. the speak and spell was a talking toy in that when a button was pressed a voice would say the letter to you. it also had spelling games and a primitive version of hangman programmed into the unit.

as far as circuit bending goes this toy is a tried and tested classic. the reason for this is its over complicated way of producing sound. while most talking toys these days come programmed with preset voice samples, the speak and spell actually synthisized the voice that you hear. this was done using three large ics on the main board (this is different to most modern toys which use the infamous "black blob" which is almost un bendable.) these three ics computed the induvidual sounds that we make in our vocal chords to pronounce letters and words. for example when we think of the letter q it just ciomes out as it is. Q. the ics in this uinit synthsized the induvidual parts of this seemingly simple sound.

the letter Q is made up of 3 sounds.

1 - k

2 - he

3 - uh

K - HE - UH

By using such a complicated method of voice synthisis the speak and spell is one of the most easily circuitbent instruments around. The seperate sounds are easy to split and mangle together by touching two of many points on the board.

These are the features that i have wired into my own speak and spell (pictured)

1 - the knob on the top left controls the pitch of the whole instrument. this can go form fast chatter down to the very basis if digital sound, clicks, bleeps and static. when the resistance is to high ( lower pitch) the lcd display stats to flicker and display random letters. any further resistance cause the toy to crash.

2 - when the toy crashes it is important to cut the battery suply imideiately. this is the same for all toys that crash while bending. when a toy crashes either the ics have over heated, the pcu has reached its limit, the clock signal has gone too fast or slow or two points which shouldnt be connected have. (positive power to ics for example) by cutting the power suply the board has a chance to reset. this can be done by turning the unit on and off again or better yet removing the batterys. however this can take time. by wiring a "push to break" button ( current is connected until the button is pressed) the flow of power can be cut instantly broken by one push. this button is the small black circle near the lcd display.

3 - the four switches on the left trigger induvidual glitches. The top one sets off a slow glitch of random gargling noises that lasts a few seconds. the other three start short glitches that last less than a second. once a switch is flipped pressing a letter will cause the glitch. these can also be used in conjunction with one another. ( 1 with 3 / 2 with 4 / 2 with 3 etc..) to create more elaborate glitches.

4 - once a glitch is running the button and switch at the bottom right can be uszed to start a loop. these two parts are called "audition and hold" .the button and switch are wired paralell so when a glitch is running you press the button to start a loop. if you dont like the loop you can quickly press it again while the sound is still runing to get a new loop. when a nice loop is found you flip the switch to hold the loop in place.

5 - the button and knob at bottom left start a single continuous tone. the pitch of this can be chancged with the pitch knob at the top right. the knb next to the button controlls the volume of the tone.