Casio SA-1 & PT20

[GrooveCriminals]

Next up is the chip in the centre of the board

[GrooveCriminals]

And finally the cut jumper (just like the Paul's other image)

I've also done one of these myself (exact same bends) and although the chips looked different it all worked fine (although the original's deep crash button seems to produce better audio madness)

Hope that all made sense 

[djsynchro]

Hey! Thanks for those. I got the voltage drop , and i found a connection that howls, but with a potmeter it now works tgether with the voltage drop to make the most unbelievable screaming distortion I mean like 8 bit Jimi Hendrix. next time i open it to incorporate those I will post my bend.

I have to say the SA-1 is ultra amazing, I love it, even sample its sounds without the glitching for my music.

[GrooveCriminals]

No problem!

I've a huge soft spot for the Sa-1 as well - the deep crash switch rarely fails to provide some kind of looped, crusty audio madness 

look forward to seeing your bend as the more the merrier!

[djsynchro]

Here's my screaming bend, I have a 4700 Log potmeter with a 5600 resistor in parallel, because I had no other potmeters when I did the bend. somewhere around 2 or 3K will probably work best. The bend works well with the Voltage Drop, it's possible to get a screaming distorted sound that still tracks the keyboard.

By the way, tried the Deep Crash F@#%N awesome!

[Circuitbenders]

Lets sit back and watch the price of SA-1's on ebay go through the roof

[Zmaupzy]

Hi here, I'm completely new to circuitbending, but a when I visited a friend the other day he showed me his mods to the Casio SA-1 and I was astonished by the magical sounds this little apparatus was able to produce randomly after his treats. Weird melancholical tunes that never were heard before, strange beautiful hypnotizing loops. It's fantastic! This is the thing for me! However, since the SA-1 is not easy to find, I was wondering if anyone can tell me what other machines have the same or even better performance after circuitbending as this little beauty? And what are the risks? Can one ruin his stuff eventually? Or is it always quite safe?

[Circuitbenders]

Most lower number casio SA's i've tried bending will do the same kind of sounds with a voltage drop crash knob installed.

Its always possible to accidently kill something while attempting to circuitbend it but once you have a stable mod installed that has roughly the same effect every time its unlikely that mod will damage anything.

[Zmaupzy]

Most lower number casio SA's i've tried bending will do the same kind of sounds with a voltage drop crash knob installed.

Okay, then I'll buy a shitload of SA's and will start bending. Thanx...

[Zmaupzy]

Most lower number casio SA's i've tried bending will do the same kind of sounds with a voltage drop crash knob installed.

Can I circuitbend the Sa-3 about the same way as the Sa-1? I can get one for cheap and I was wondering if these models are similar? Please let me know, I'm about to buy it and my fingers are itching to do the job!

[Signal:Noise]

I've just bought an SA-1 for my first bending project, even though I've not opened it up yet this thread has been hugely helpful.

[Circuitbenders]

Can I circuitbend the Sa-3 about the same way as the Sa-1?

no idea, seems likely, but if you find out then post the result here

[Zmaupzy]

Can I circuitbend the Sa-3 about the same way as the Sa-1?

no idea, seems likely, but if you find out then post the result here

I certainly will!
By the way, does the Casio MT-750 ring a bell to anyone? Is it circuit-bendable?

[Signal:Noise]

Got my SA-1 today, spent a bit of time poking around and found some interseting bends, one which is a high cut with distortion, thing is it uses the same pin as djsynchro's distortion mod, is there likely to be any problems running two wires from that?l

[andy_wheels]

thanks to everyone involved in the useful info found here about the lovely sa synths. 

i've now bent a sa-1, an sa-5 and i'm about to get funky with a sa-65.

they all look like they're based on the same two chips:

oki M6387
AN8053

the sa-65 has the same size circuit board as the mini sized sa's, it just has a big case and larger keyboard! i'd guess all the keyboards in the sa range have the same basic setup with other features added on.

i've found the deep crash on both the sa-1 and sa-5. it's incredible how varied the sounds are that it creates, some of the drones and beats make great samples and loops. for the sa-1 i used the photos in this thread as reference for the pin connections but did a bit more exploring on the sa-5. it looks like the deep crash is triggered by a variety of shorts on the circuit board and can often be triggered by simply soldering up a body contact. it often seems that a very quick short produces the most interesting crash so it's worth trying out different ways to make that trigger and not just throwing in a switch.

infact, i'd suggest body contacts are well used on these keyboards. body resistance seems perfect for some of the buzzy bends which are a bit too extreme if connected with just a switch. if you're looking at the board with the keyboard at the top, try connecting a large body contact to the lower pin of capacitor C5 (c393 in djsynchros pic?) and make up another large contact connected to some/any/all! of the last few pins on the oki6387. i've connected up pins 29 and 30. holding the two contacts (large bolts in my case) produces a lovely buzz which oscilates with the rhythms and sounds of the keyboard. the more you hang on to the bolts, the bigger the buzz. yummy.

the only issue i have with the sa's is the way the batteryies fall out when you open them up! must buy a battery box next time i go down maplins....