Thursday, February 9, 2017

THE INFAMOUS KORG POLY 800

























Last summer I borrowed my friends Poly 800 for a test ride and a cleanup. I read about the Moog Slayer mod from the website synthmod.net and I went ahead and did it. After plugging the thing in and jamming a bit with it, I was like, f........k me, I need one of those! It sounds very lofi, yet very interesting. It's got that sort of in between a Casio and a Poly 6 sound, very cool stuff. I asked him to sell it to me, but he didn't want to. So after a while I gave it back to him knowing I was going to find another one at some point. So, a couple of weeks ago I got a call from my crate-digger-friend Nico who was in a independent thrift shop in Montreal and was like: Hey man! There's a Poly 800 here for sale but it doesn't work. We tried to plug it in with a 9v adapter and nothing lights up?? Immediately I knew they we're plugging a different polarity into it so there was hope. Ether it was fried or perfectly working but not the right plug. She was asking 25$ for it. I told him to get it. Worst comes to worst I would of wasted 25$ and maybe make a bit of money selling the good parts.

20 minutes later he shows up at my house with the thing in his hands and it looked pretty good. The joystick and all the keys were still there. That's usually a good sign. He had bargained it for 15$. So, I plug it in with the proper adapter and the lights were on but no sound. It was dirty as hell so I thought that maybe if I give it a good clean up, maybe it would play something. The lights were on, thats good enough, it was not burnt out, my gut feelings were right about the polarity I guess. The next day I open it up and it looked like a shit storm in there.



I started by cleaning it up roughly just to see if it was worth the trouble to dismount it all and thoroughly clean up every part. I plugged it back in, went through the presets to see if anything was coming out. I could hear some noise coming out as I pressed the notes but most of the presets were gone. I could hear the oscillator of preset 14 and the modulation and all, but it was faded. I went through the parameters and I programmed a bit of a sound, so life was still in there!

























I dismounted the whole thing, removed all the PCBs, buttons, etc. The main frame and the keyboard (all electronic components where removed obviously) had to soak for a few hours in the bathtub. There were signs of acid leakage from the batteries through various parts of the boards. I took alcohol and Q-tips to remove it. Luckily, no chips were affected by it. Notice on the first picture of the inside (top) that there is a circle on the main module board that looks like a place for those 3V batteries, only no signs of batteries? I remembered from my friends Poly that his had the batteries on it. So I knew the leak didn't come from there and I also figured that because of the absence of batteries there, the memory was probably wiped out, resulting the absence of sounds from the presets.






One of the ribbons was damaged. I don't know if it was related to the battery leak or something fried, or whatnot? One of the connectors was broken and it looked like the 2 first pins were burnt and cut out. So I cut the 2 affected wires and re-soldered them directly on the board.   



 

After endless hours of cleaning and troubleshooting, I reassembled the boards back and plugged it in. Now the whole thing seamed to work. The presets were still not there and some of the parameters were not working. Mainly the second DCO actually. None the less, it was working decently enough for a 15$ thing. I was willing to be in peace with a more than half working Poly 800 for that price. Now before I put the screws back on, the fun part was to be done. The classic Moog Slayer mod. There are other mods that can be done on it, but I tried a couple and it made it sound kind of bad. I'm not really into the lofi sounding circuit bent style engines for my personal music. Just the Moog Slayer mod is sufficient for my needs. If you research on it, you will find all kinds of fun stuff to do with it.

I'm not going to in details about the mod, because the guy at synthmod.net pretty much covers it all in details. I simply followed his instructions to do mine. I really recommend that you do it if you have the Poly 800, it truly changes the game. You can really make it sound great and it becomes more fun to play with. A little note on it, the cut off and resonance are still active in the programming. If you want the full effect, you have to put both of them at the highest settings to have the full range of the potentiometers. Seriously, beware of the resonance, it oscillates like crazy when you put it up at full speed!

PS, If you live around Montreal and you are not at ease with electronics, you could also pay me to mod yours! Write me a message and I'd be happy to mod it for ya!


















































At last, the mod was successfully done and all the screws were put back in. The synth looked almost brand new. Now it was time to put the factory settings back into it. I went to research how to do it and it was somewhat easy. I found a few videos on Youtube about it and I tried it and it was not working at first. You have to put the thing on TAPE mode and basically run an audio program through it. You can find the original wave file here. Some people recommend that you record it on tape and do it like in the old days which makes sense. However, I manage to do it directly from my computer. You might have to play a bit with the levels from your sound card. I have an SPL Crimson sound card and I played the sound from the headphone jack with the volume level set to 12 o'clock.

I went back to check the presets and they were all there! The second oscillator was also working. The synth works like a brand new one! I spent that evening programming all the settings as I pleased and adjusted all the cut off and resonance to fit the mod for each presets. I couldn't believe it, a lot of work plus 15$ got me a "very good" synth!

The next morning I fire up the thing and NO MORE SOUND! WHAT??? Then I remember the batteries missing on the PCB. Oh! right! No more memory again... All my programming was gone. I read about that problem too and sure enough, there is 2 versions of the Poly 800. The mk1 and the mk2. My friend had the mk2 which had the batteries but mine is the mk1, no batteries. The only way to have its memory was to put C batteries inside. I didn't want the C batteries, so for now I simply took the wires connecting to the battery compartment and installed a 9v square battery instead. I don't use it without the power adapter anyhow. It works for now. I will solder the 3v battery thing on the PCB at some point, but now it's time to jam with the thing!

Wednesday, January 11, 2017

GUITAR PEDAL BATCH 2017




















I made my first batch of guitar pedals for this year!

- Heartthrob Tremolo
- Proco Rat
- ZVex SHO

All circuits are from Guitar FX Layouts
http://tagboardeffects.blogspot.ca

Monday, May 23, 2016

PORTA-SYNTH 01 - A FRESH NEW START

The past few years have been a real transitional period for me. After years of being an active musician, tape label owner and working a full time job, I hit depression followed by a burn out and ended up on EI after I got laid off from work. I decided to put a hold on my music activities and set the label aside. During my recovery I started getting back into something I briefly started years ago, my passion for electronics and DIY instrumentation. 









My grandpa and my dad taught me how to solder when I was young and I've soldered basic things pretty much all my life. I never got in-depth with electronics apart from a bit of circuit bending and fixing basic things on appliances and instruments. I discovered the Music From Outer Space (MFOS) website and ordered a few PCBs to start with. I first built the Echo Rockit, then the Mini-Synth, then the Sample and Hold. I then ordered and built the Ring Modulator and the Phaser. I received a copy of the book Handmade Electronic Music by Nicholas Collins as a gift and started reading more about DIY stuff. 








Soon after I started regularly making electronics, Ray Wilson (owner of MFOS) unfortunately got sick and had to close his shop. Since I couldn't order more PCBs from him, I started building perfboard circuits to be able to build more modules independently and to improve my soldering skills. After months of trial and error, I got a few modules working. With the help of my dear friend Al Isler (musician/engineer) who designed perfboard layouts based on Ray Wilson's schematics, I was able to make a few more things to add to the system. (I will post another article with these layouts for DIYists to build. They're very cool :)



After months of building, I had my system mounted on wooden racks, which I constructed by hand. I tested a bunch of modules and designs and kept the best ones for the portable system. I will eventually rebuild the racks with fresh new modules. Possibly CGS stuff. Anyhow, I messed up most of my builds and it was quite frustrating at times. Lots and lots of troubleshooting, filtering through found circuits and all. I had two little metal suitcases laying around, perfect to house modules, so I decided to use them to build a portable system. A system that will most likely be used for droning, texture making and shaping sounds and samples.

Here is the list of what my system has:

- MFOS Echo Rockit
- MFOS Sample & Hold with VC-Clk
- MFOS Ring Modulator
- MFOS Noise Toaster VCF
- MFOS Echo Rockit Resonant VCF
- 2X MFOS AR Enveloppe Generators
- 4X MFOS Noise Toaster VCAs
- 2X MFOS Signal to gate converters
- 4X 40106 Oscillators (inspired by Nick Collins)
- 2X System 100 LFO clones 
- Digital Delay (Boss DD3 modified and rebuilt into my systems format with better parts).
- 3X ZVEX SHO preamp clones
- 4-channel audio mixer
- a utility panel containing 2 attenuators, audio and CV splitters.

The audio signal is 1/4 inches and the voltage is controlled using banana plugs. We could call it the MFOS format maybe? It's between east coast (Moog) and west coast (Buchla). At first I was making a total east coast 1/4 inches for everything on the synth, but I got seduced with the idea of controlling voltage with smaller, stackable cables. 


I haven't made my own music for more than a year now and I'm super excited to start up again and make an album. I will be releasing the next phase of the Élément Kuuda journey. With explorations of new sounds and new ways of working with my custom system, it should be quite interesting.








Wednesday, March 23, 2016

AUDIO MIXER MODIFICATIONS

A little mod I made for my friends console. I took a Gemini MX881 mixer that had RCA plugs and I replaced the plugs for 1/4" jacks. I was lucky that the holes in the back were big enough to fit the jacks. So no drilling action for this one! Now he can use the mixer to plug his synths in his studio!

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