CASIO MT-205

[jamiewoody]

i was recently GIVEN one of these by my niece who "outgrew" it. (she is 15, i am 41!). ;-)

one thing i took note of right away, was when the main volume is all the way up and the accompniment volume is down, you get this sweet distorted sound out of the auto-chord!!!

so far, this is what i am dreaming up for this keyboard: pitch control pot, speaker out...

did anyone ever make a schematic for bends for this baby?!

i'll have fun probing for bends!

[jamiewoody]

i started bending this baby tonight!

i added two 8 point patchbays. check out this scene: half of the bends i discovered were an echo chamber! i can play notes and they repeat. depending on how i have the patch, i can keep adding notes to the loop!

i found one or 2 distortion tones, but, in the other 8 point patch bay, i discovered envelopes! kinda cool. since this was "there", i wonder why it wwas not included like on the factory sk1?

i am not finished yet. i want to get a pitch control out of this, and maybe another "twister". 

also, the power on/off switch is acting kind of weird. i have to figure that one out. casio switches pretty much suck anyway.

[jamiewoody]

so, does anybody know anything about these keyboards? it looks like there are 4 drum pad inputs. do they have to be "casio", or can they be a homemade trigger?

this thing is amazing! i can set sound loops by using the patchbay!!! i think i feel an ambient music project coming on! 

[SineHacker]

could you post a video or some recordings, sounds pretty sick!

[jamiewoody]

good point, i really need to do this. unfortunately, i have dial up at the moment, which pretty much sux!

i think i will be making a circuit bending website for my projects soon.

[jamiewoody]

there didn't seem to be as much in the way of glitchtones.

i  was able to change the envellope with the patchbay. and another with the echo-loop thing. i think i will call this the "automator".

i wish i knew more about these. any other groovy things i can do to this thing? a pitch knob would at least be cool.

the plan is to build a case for it and have the controls on a panel in the back for easy bending.

there are drum inputs on it too. lots of reserch to do.

[SineHacker]

I didn't know dial-up still existed  I hope you don't pay by the minute as well! my dad used to make me give him my pocket money in exchange for internet time 

good job anyway

[jamiewoody]

i'm working on making a circuit bent website for my projects. it will become more comprehensive as time passes.

i've does 4 keyboards thus far.  this mt-205 is a work in progress.  i want to at least get a pitch control out of this badboy. i thought of wiring a pot to the tuning trimmer, but for some reason, it is a *!&*~ trying to get  the board out of this!  and i do not want to force anything.

any tips on a pitch control for this? the closest thing i have come up with is a sub-octave control, which seems to slow the clock down. (i say this, because there is a slight delay when key is pressed). simply turning this know gives this really glitchy effect!

(forgive me if i get my definitions wrong, as i am making discoveries, some i have not seen documented, though i am sure i am not the first).

one patchbay seems to open different envelopes. i can sustain, dampen, distort, etc. this makes me wonder if they had plans for this keyboard which never saw the light of day?!! these are features in the sk1!!!!

the other bay loops what you just played!

i ran out of screws, so i ducktaped the patchbays! LOL!  i thought of covering the whole thing in ducktape, for that space age look! ;-)

[Timodon]

Hi Jamie

I've got one of these keyboards - so far I've only gotten a few distortions and a sweet tuneable feedback pot. There are also some weird pulsing glitches on the main ICs some of which can be controlled with pots. More stuff on my MT220 (similar chip?) - Lo-pass filter control and overtones.  Breakbeatnazi found a bunch of other mods on the MT205 though check out this thread:

http://www.circuitbenders.co.uk/forum/index.php/topic,827.0.html

he definitely mentioned sorting out pitch control which I too am interested in - I think it's just what some of the folks round here would called a "Simple" case of replacing the clock crystal with a controllable oscillator pulse made from a 555 IC, a couple of Capacitors, a resistor and a pot.  I'm very much a clumsy novice at this bending lark so I haven't yet plucked up the courage. I have a bunch off 555s sitting in a drawer waiting for me to get on with it when I have some time. I'm not up to speed on using capacitors yet so I might try an APC or something first just to get a feel for it before I go ahead an get rid of the precious crystal on my casio!

It sounds like you've found loads more than me though so any chance of some pointers on the dampening/ sustain and echo chamber stuff?

I once managed to make my MT220 (which has exacly the same sounds so probably a very similar synth chip) crash in such a way that the release envelope was permanently turned off. Turned the piano sound into this gorgeous floaty chord pad that just kept on decaying forever.... I'd love to work out how to get it back but I lost it next time I turned the power off 

[Timodon]

so, does anybody know anything about these keyboards? it looks like there are 4 drum pad inputs. do they have to be "casio", or can they be a homemade trigger?

this thing is amazing! i can set sound loops by using the patchbay!!! i think i feel an ambient music project coming on! 

I've got the drum pads - they are like drumsticks with the rubbery "Pad" at the tip of the stick - when you hit them off a surface (or even just wang them hard through the air) they trigger the drums. reasonably sensitive, you can do drum rolls with them.

I've been looking for an alternative way to trigger them, as the trigger inputs are on 3.5mm I wondered if audio signals would work... tried playing noise down each channel but so far no luck. I might try recording the output from the drumsticks and see if that will trigger the drums when played back from an external source. If it works I'll post the sound files, it shouldn't be too hard to sequence your own beats if you have a four track or sonething!

[jamiewoody]

i have heard there are lots of cool things to do with the drum features on this one. i'm not a very good drummer though. ;-)

i like how i can make this loop notes by using one of the patchbays.

and i still have not ruled out taking this baby apart again. i think there HAS to be more in the way of cool glitchiness!

[jamiewoody]

i think i am going to have to take this thing apart again and poke around. i am finding, with these old casios, everytime i think i am done, and curiosity gets the better of me, i end up finding more and more things to do!

plus, i took the speakers out of this one, so there is lots of room for controls, pots, switches, etc!

[Timodon]

So Jamie any chance you could share any pics or schematics etc? I'm very interested in the dampening/ sustain and echo chamber sounds that you mentioned!

[jamiewoody]

yeah,you are correct, sir. i need to take pics of stuff. i need a better digital camera, the one i have is built in my camcorder, and is only 1.3 mp...pretty lame.

i would actually have to open this thing back up and look at what i wired to find the bends. i was pretty amazed at the bends i found though!

i think soon i will open it back up anyway. i am always amazed at how many bends casios have and how i always find cool things when i open them the 2nd time!

[Timodon]

Cool  I'm going to try out the audio triggers for the drums tonight I'll let you know how it goes...