Ensoniq SQ-80

djsynchro · May 15, 2006, 11:29:51 PM

Hey Paul...

For over 10 years I have an Ensoniq SQ-80 and today I looked at it and I with a SHOCK realised that the sound engine is 8-bit digital (with CEM resaonant analogue filters) and if I could just get the waves to glitch without it interfering to much with the rest of the synth engine (envelopes etc.) that could be KILLER.

First thing first: I used to be a lighting technician so I would be taking all proper precautions, stay away from the power supply/capacitors, work with gloves & goggles and so on!

Anyone reading this: Do NOT attempt to circuit bend anything that runs on mains voltage, unless you know EXACTLY what you're doing! Even if it is disconnected from the mains you could still get a shock from a charged capacitor!

Now then. What I would want to try and do is get the waveROMs to glitch and nothing else, because i do NOT want to fry this classic synth. This is my question: The 4 wavechips are EPROMs... do you think that shorting them could wipe/corrupt them? If so I might still try it but I'd try to first get a set of backups then. (There are still parts for the SQ on the Internet so that might actually be possible.)

There is also a cartridge port for connecting an EEPROM (Electrically ERASABLE programmable ROM) do you think shorting that would work like you suggested for the MD-16? Is that because all the datalines for all the memory stuff is all connected together?

Cheers!

Circuitbenders · May 17, 2006, 04:21:18 PM

I love a bit of Ensoniq action. Like early Kawai they had a habit of making massively underrated and over-engineered bizarre equipment.

Messing with EPROM's is going to be very risky i suspect, and you do not want to be permanently corrupting the waveform data unless as you say, you have a set of copies to replace them with. To be honest i'm not that knowledgeable about working with EPROM's, i take it they are mounted in IC holders so they can be removed and upgraded etc. I'd imagine if you track the circuitboard traces you'll find they link directly to the cartridge port.

Basically if someone asked us to circuitbend their SQ-80 then i'd probably say no as it was to risky, but if it was mine i'd probably give it a go anyway, thats the wonderful world of circuitbending

djsynchro · May 18, 2006, 01:02:07 AM

I found some terribly interesting info on the Net! There are 74 waverforms in the SQ80, and by manually editing that number in a sysex dump to somewhere between 75 and 255 the synth will "look" at different sections of the ROM which will mess with multisamples etc, but apparently this way the oscillator will also look at program data, and use it as sound!

When I have time I will have to try that out, that will definitely sound noisy. A soft bend so to speak.

Thanx for the tips on the EPROM, will investigate more and get some backups before attempting bends I guess.
Did anyone ever bend an Atari ST? maybe the video will be cool... i still have an old Apple (pre power PC) as well.

Circuitbenders · August 19, 2006, 03:38:47 PM

I might have the chance to get hold of one of these and was wondering if you ever got anywhere with bending it?

djsynchro · October 15, 2006, 11:15:22 PM

About the "soft" bending:

I found an editor where you can set the wave to the "wrong" number and... NOTHING happens.
Bummer. Apparently it can be done by dumping a sysex patch, manually editing the wave number with a HEX editir and dumping it back....jaaaaaa well didn't get around to doing that yet.

I haven't tried circuit bending it yet, because... I really don't want to break it. It's my master keyboard, a really specialy hybrid digital/analogue synth. I think a friend of mine has a ESQ-1 with a failed keyboard... That might be a contender (trigger it from MIDI, circuit bend it). There is a website where they even have spare parts and stuff...

As for the sounds being in EPROMs that should be OK, the drumulator I bent has EPROMs, they don't mind some bending. I think EPROMs can be erased with ultrviolet light only?

Shit... writing about it I really want to do it... it would be a first on the planet I think

If it CAN be done it would be awesome, the engine is 8-bit digital but the filters are analogue

djsynchro · January 12, 2010, 03:43:29 AM

OK this is sad now... Someone gave me an ESQ-1 which is very similar to the SQ-80 but no drums/attck transients just single cycle loops. Actually synthwise, to me it's just as good, but for bending the SQ-80 would be the ones as it has really primitive attack phases and percussion... but they're fairly rare and I'm selling it for quite a good price :-( so bending it booooh.... maybe I should quicly short the sound chips with a resistor if I get the most amazing sound I have EVER heard I could still cancel the guy....

Dear reader what would YOU do?

Gordonjcp · January 12, 2010, 11:50:22 AM

The CPU on the display PCB is quite fragile, and irreplaceable - so be careful!

The rest of the synth uses fairly standard parts. Even the DOC chip is kind-of available. You can download ROM images from Rainer Buchty's site - http://www.buchty.net/ensoniq/ - including being able to access the "hidden" waveforms.

djsynchro · May 09, 2010, 12:02:34 PM

The sale fell through so I still have the SQ-80 and the ESQ-1. Since it the standard thing (making connections on the waveform ROM) bending shouldn't break it (but boys and girls, stay away from the + and ground connections on ICs - consult a data sheet if you can find one, )

To be continued!

Gordonjcp · May 09, 2010, 06:38:54 PM

On the SQ-80 and ESQ-1 the waveform ROMs should be the only ones you need to touch. They're immediately obvious. Stay off pretty much all the rest, you'll end up crashing the CPU and losing all your patches.

Since you can get some pretty extreme noises out of them by tampering with the patch dumps to allow access to the "hidden" waves, I wouldn't even bother bending them ;-)