Casio SA-1 & PT20

[djsynchro]

@ djsynchro ; i followed your instructions (100 ohm pot in line with the deep crash) and you're right,
it is a must have !!

Told you! Glad you like it 

[djsynchro]

An SA-1 built as a present so I decided to decorate it. It's so ugly that it's pretty,
I hated it at first but it really grew on me. Will be hard to let go of, glitches better than mine too.

[Orangery]

The paint job looks great... bends good too huh?

I included a voltage drop crash on my SA-20... works best when the keyboard has been left on a while.  I've also (very badly) wired up a Casio SA-8... works ok but it looks terrible... wires everywhere and the case doesn't shut.  I really detest soldering!

BTW... what other keyboards apart from the Casio SA series generate random chance compositions?

[Circuitbenders]

  I really detest soldering!

You may have chosen the wrong hobby there then 

BTW... what other keyboards apart from the Casio SA series generate random chance compositions?

If i recall correctly theres a whole series of Realistic Concertmate keyboards that appear to be direct rip off's / rebadged casio SA's, but they seem to be built with cheaper circuits and components. Never tried bending any of them though.

[iqoruvuc]

BTW... what other keyboards apart from the Casio SA series generate random chance compositions?

The Casio MT-140/240 do some pretty far out stuff, though slightly different from the SA range.  I can't recommend them enough! : )

[Orangery]

Yes, the Casio MT-140 is featured in Ghazala's book... looks a bit old fashioned though!

I just picked up a Yamaha PSS-30 but I've found nothing interesting with it.

[zoomtheline]

I've posted about a yamahaPSS190 in a separate topic today, and in it I have put what I have done to an SA-8...

I had not found any info on bending these so just tried myself to find some sounds......I think it is basically like the SA-1/2/5 (please correct me if I am wrong though) but laid out slightly different...but the elements are not far off...
Question is, would it be possible to add these cool bends I have seen in this topic?
I hope so because if it adds another element to what it can already do.......Its going to be a beast!!!
cheers.

[hippyjon]

ive been bending an sa1 as is described. i was  putting in the deep chrash and the whole unit just stopped working, i get nothing coming form the speakers at all not even hiss. it was working fine up until this point. ive taken the deep chrash out and made sure there is no solder connecting any pins and i still have nothing.

im wondering if ive fried the chip how can i tell? would the unit not even switch on if the chip had gone,  surely i would get some hissing.

does anyone have any ideas what ive done wrong? i really hope its not dead it was was starting to sound good   

[andy_wheels]

it's impossible to tell from your description what has gone wrong with your sa..

..but, i can say that i've bent quite a few of them and have never managed to fry any due to modding up the crash functions, or any other bends. they seem rock solid...

so, i'd make sure you've covered all the possibles... power supply/batteries, solder touching pins, loose wires etc before deciding if your little friend is dead...

[screenhousemusic]

make sure you check all the obvious things, like battery connections & batteries etc!

[hippyjon]

cheers for the help i figured it out the on switch wasnt connecting with the board because of a cable tie id used.

ive installed all the bends on this forum and it sounds wicked so thanks to everyone whos posted     

[computer at sea]

Thanks so much to everyone who has posted on this board!  I've been bending for about a year and had somehow never heard of the voltage drop mod.  What a great technique! 
My SA-1, which I hadn't had much luck with before, is now in top form.

[iqoruvuc]

Here's a must have effect for any SA-1 - I just tried it today and it sounds awsome.

First of all you must have done the following mods (all have been discussed prior on this thread):

a) the sa-1 must have the voltage mod crash, or some other bend that causes the machine to crash.

b) the 'dj synchro distortion mod' should be installed.

If you have a SA-1 with both these mods then I urge you to build a LFO with a 555 and DIY Vactrol and then run the (+) side of SA-1's audio through the light dependant resistor side of the vactrol before connecting it to the speaker or jack.  The 555 timer circuit will need to attached to part of the keyboard somewhere to gain its power, preferebly configured so you can turn it on and off with the keyboard's power switch.

When this is set correctly the DIY LFO will act as a 'gapper' effect on the audio and you can change the rate by the pot.  Just playing the piano or synth waves sounds good.  However what really sounds amazing is if you crash the keyboard so you have white noise or some thing similar - you can then sweep the noise with the distortion mod whilst simultaniously lowering the rate of the gapper, then when it's most distorted (and missing the high frequencies) you can decrease the distortion whilst increasing the rate of the gapper.  It sounds very cool - try it!

[treefingers]

hiya i am a new user to this site but have been bending stuff for around 3 of your earth years!!!!

but seriously the pt20 (concertmate 300) is possible to bend i had one for a whille and gave up but went back to it after a few weeks ans now it has a tone control of an octave either way and have set this up on a pot. this increases the tempo of the drums and because you can slow the drums with the tempo buttons still you get some almost broken slow glitch noises from the drums. the pot also controls pitch for an effect just like a theremin and with the audio out can be effected. very stable and working. add to this the dostortion switch off/on this glitch effects the drums and makes for some very interesting backbeats.  also this controls the theremin sound thus giving a built in distortion pedal great. will post some pickies soon. cheers.   


ps am also looking into putting circuit bent pedals into ALA matt belamy but circuit bended!!!

[mk23]

Hi all,
I have been following this thread over the last year and recently  I finally dug out my SA-20 from the pile of junk for some bending action. Thanks to all the useful tips here I've got the deep crash and voltage drop bends working fine. I have been having lots of fun, so thanks a million for all the great documentation.

However, I have been poking around trying to find the screaming bend (see DJsynchro's post) without much success. I would like to ask if anyone:
a)   Has found this on an SA-20?
b)   Or, who knows roughly what resistor the 3k pot is connected to? (so I can narrow down my choices on the PCB)

Thanks in advance for any help

Dave mK