Oakley Discontinuity Module Graphs

I promised you to show a bit more about what the Oakley Discontinuity can do. To begin with here is a picture with the finished module in my cabinet. If you click on the picture you can read the text with the controls. The controls I used in the examples below are: Treshold, Fold, Discontinuity and Offset. I only use the normal output (so not the Clamp or Clip) and I put a Triangle wave from the PC function generator on the input. I'm not going to describe what all the individual control do. You can read the Oakley manual for that ;) But just some examples to let you see what it can do. I used my Velleman PC oscilloscope to capture the output signals btw. It has a nice 'save as' option for the image you have on your screen :)

So here is the signal that I put in:

And this is what came out:

I'm sure you can imagine that that will sound different :)

Yusynth (Part 23)

A very small Yusynth update. This morning I completed another 1U Yusynth AD/DC mixer module. Since I already did a post on this one I didn't think I would show how it is build again. One thing that is different though on this one is that I was out of 50K potmeters and I had a lot of 25K potmeters left. So I sent Yves an E-mail to ask if that was OK. And he responded that this would work fine. So I build it using these potmeters and it works great. In the picture you can see the 3 Yusynth mixer modules I build so far. The right on is the 2U version. I still have one PCB left to build another 2U version and I think I will do that since they will come in handy for sure. I just need to order another front panel for that one then.

Oakley Discontinuity Module

Yesterday I finished another Oakley module. This time an module called 'Discontinuity'. Basically it is a Voltage Controlled Wave Folder. It changes the shape of the signal you put into it and it generally creates overtones. I will show you later with some examples. Almost all the parameters are also voltage controlled which makes it possible as well to keep a sound continuously moving. In the picture you can see the module from the back. As you can see there is a seperate PCB again for the potmeters and jacks. But on this picture the jacks are not installed yet.

And here is a picture of the finished module. Here you can also see the extra PCB with the jacks. I chose to hard wire all the connections between the PCB's. You could also use connectors so that you can take it apart easily, but I didn't see the added value in that. First of all I don't plan to take it apart. The PCB is even reachable from the back in case of a problem. Secondly I don't like putting these kind of connectors on wires. As you can see I wired the most right set of wires a bit too short. I couldn't even put a tie wrap around them anymore. But I decided to leave it this way, because it will work fine and desoldering will make more of a mess I guess.

And then it was time for some testing and calibrating. First the usual smoke test with no problems. Then I put a signal on this input from the PC Function Generator and tested if I heard something on the output. That worked fine. Then I tested the CV inputs and actually got three of them that didn't work. I started investigating by measuring on the PCB and found out quickly that I forgot to wire three wires :) Well keep reading that documentation sometimes ;) After I installed them I even found out that two of them were the wrong way around. And after I twisted that It all looked OK.

After that you really need an oscilloscope to do the calibrating. In the picture on the right you can see an example of what it looked like when I put a triangle on the input and twiddled around a bit. I will do another post later on with some more examples so you can see what it can do. I have a speaker on the output all the time and you can really hear the difference. Normally a triangle sounds very soft just like a sine wave. After putting it through this unit it really sharpens up the sound and you can make some interesting stuff from very basic waveforms. OK. As promised more later. But for now it seems to work fine :)

Oakley MidiDAC Midi2CV Module

I know that I'm posting updates on finished modules very rapidly after another now. But that doesn't mean I all build them so quick :) I have build a lot of PCB's the last two years and just now I have all components for some modules. So that is why I'm able to get them finished so quickly because now I finally have the potmeters or the front panels. Here you see the PCB of an Oakley MidiDAC midi to CV converter. It is supposed to be very good so I'm very curious how it will track later on. I should eventually hook my midi setup up to my modular through this unit.

Oakley thought very well of the layout of the PCB in correlation to the position of the front panel components. They can do so of course because the PCB is front panel mounted through the potmeter so you will actually know where they go :) But because of this the wires are all quite short which makes it look very tidy. I just couldn't use my regular led holders because one of the leds is exactly behind the PCB. I guess that is the downside of this construction for me. I used more simple black plastic led holders for this unit and decided to just solder wires to the leds in steads of bending the legs and soldering them on the PCB itself.

Then is was time to hook it up and to some testing. At first I didn't get any response but found out quickly that this was because the Midi channel was set wrongly. The DIP switch worked just the other way around as I expected. Then I hookup up a midi keyboard and started to test all the signal outputs. As you can see there is a lot of them and that is also what makes this Midi to CV converter great. Next thing was to check the switched and potmeters and that all worked fine. So then it was time for some calibration. Of course this module must tune and to 1V/Oct.

Calibrating isn't even that difficult on this module. You just put the tune potmeter in the middle. Then there is an initial trim potmeter. And then you measure the Voltage on the Pitch output. Select the lowest note possible and it should read 0 Volts. Then you go to the highest midi note possible and then turn the V/Oct trim potmeter until it read 10,58 Volts. And then it should track. And I verified that by hitting notes across different octaves and it tracks perfectly. I was expecting this to be much more work, but actually it tuned in about 5 minutes :) After that I played around a bit on the VCO I build recently. I was thinking to recalibrate that VCO soon using this MidiDAC since I think it tracks even better than the Roland CV keyboard that I used back then. If you are interested in this module visite the Oakley Website at: http://www.oakleysound.com/mididac.htm

Oakley Equinoxe Voltage Controlled Phaser

Tonight I finished my first Oakley module. It is a Voltage Controlled Phaser module called Equinoxe. And it is called after the Equinoxe album by Jean Michel Jarre, because it recreates exactly the phasing of the originally used EHX Small Stone I guess. It is a fairly simple unit to build and luckily I had some components in stock for it like the LM13700's that I got long time ago already. As you can see this module is not on a potbracket like my other modules. Oakley uses PCB mounted potmeters that come with special brackets to make them stronger. And you can use them to hold the PCB in place.

For this module I got the PCB, potmeter kit and pot bracket kit from Oakley and I got the front panel and knobs from Bridechamber. The rest of the components I could source through my regular electronic component suppliers. You can get the documentation for this module on the Oakley website by the way. After applying power to the module (usual smoke test) I started testing it. I think I did what everyone does with a phaser the first time. I put some noise in it and put everything to full and the modulation speed very low. Then you get a very neat wind sweep sound. And it did that perfectly so I guess I can say it works. I still need to see if some trimming is necessary. I didn't look at that yet to be honest. I was happy enough it worked.

And here is the finished module between some unfinished ones. As you can see it has a build in LFO. You can also apply an external CV signal for modulation, but for normal operation the internal LFO works fine. You can also use the output of the LFO to modulate an external module to have them run in sync. The other controls are Frequency, Emphasis and Modulation Depth. Next thing I should try I guess is run the Eminent 310 through it and see how it compares to the EHX Small Stone. But on the other-hand I have an original EHX Small Stone (even a Russian one) so why should i? :) Ah well just for the fun of it I guess. I have some more Oakley PCB's ready so I hope I can show them to you soon. I'm done for today :) Going to watch a movie now. Good night :)

MFOS Stereo Mixer (Part 2)

When I tested the MFOS mixer I found a problem. When trying out the stereo output and some stereo channels I found that I was missing some channels. I checked my wiring and I couldn't find any mistake there. Then I started measuring signals and found quickly that I had signal in the input of the stereo potmeters, but NOT on the output. I thought that was very strange. So I started measuring the potmeters themselves and it turned out that some of them didn't work at all :( So after that I decided to test the other set I have. They worked so I decided to replace them.

Replacing the potmeters was not very easy. As I said in the previous post it is sometimes hard to reach the solder lugs. But I first removed the old potmeters with the wires attached. Then inserted the new potmeters and then finally soldered the wires one by one so that I couldn't go wrong with that. You can see it in the top left picture. In the picture on the right you can also see that I didn't shorten the shafts of the potmeters yet. These ones are made of plastic so with a small saw you can easily shorten them even when they are already mounted.

After this I redid my testing procedure and found that everything was working OK. These plastic stereo potmeters just don't feel so solid as the metal ones. I might replace them in the future when I can source better ones. Then I encountered another challenge. These new potmeters didn't have round shafts but they have a flat side. This is normally to have the knob on at a fixed position. I found that when I put the knobs on it didn't align with the scale on the front panel. So I had to twist the potmeters a bit to get that right. You can see that in the picture on the left.

And here is the final module. It is not really that bad I think :) It works great. I played a bit around with the Mooger Froogers on the Send and Return channels even though they are not stereo. But this way I could add some sound effects to the input signal by turning the send potmeters. And of course there was one thing that I gambled. And that was the polarity of the headphones stereo jack. And of course I switched left and right. Well 50% change eh? :) I think this is quite a nice mixer and you can build is very cheap if you are interested take a look on the MFOS website at this URL: http://www.musicfromouterspace.com/analogsynth/STEREOMIXER2006/STEREOMIXER2006.php

Mr. Braska's Apollo Studio Experience (Part 5)

And here is another episode of the Mr. Braska Apollo Studio Tour. I wanted to show Mr. Braska my latest DIY project. The MB-6582 Midibox synthesizer.

I explained to Mr. Braska that this synthesizer will run on 8 SID sound chips coming from old Commodore 64's and he wanted to see them. Here you see Mr. Braska drewling on them. I think he fell in love again! Frogger memories?

Then I asked Mr. Braska if he wanted to help me wire another module. But then he saw the wires and he covered his eyes and started screaming. So I guess not :) Bad dreams about the cable mash he was in last week I guess.

But when the MFOS stereo mixer module was ready he seamed to enjoy it. He was slinging acros the wires like a little green Tarzan :)

And as promised mr. Braska reveils the whole of my modular desk. Can you still spot Mr. Braska? :) As said before all the modules with knobs on them are finished. The rest is still work in progress but I'm finishing up a lot of stuff soon. As you can see the synthesizers.com Q960 sequencers are also in place now.

And the worst news is that the desk is even too small. We will start building some extensions to it soon since I need to harness some more modules that I plan to build in the near future. OK enough Mr. Baska for today. I'll do one more final post soon to close this serie of.

MFOS Stereo Mixer (Part 1)

This weekend I started on finishing a new project. It is a stereo mixer. I used a PCB that I bought from Music From Outer Space (MFOS) designed by Ray Wilson. I designed a MOTM style front panel myself for this module that I had produced by Schaeffer. It is quite a nice mixer with 4 mono inputs, 2 stereo inputs, 2 stereo send and returns for SFX integration and it also has a build in headphone amplifier. On all mono channels you have a level potmeter, a pan potmeter and 2 send potmeters. I used Alpha potmeters for the mono channels but had some trouble sourcing stereo potmeters. But I found two sets of 6 and will see which ones are best later on.

As usual I started with the inter component wiring on the back of the front panel. All components have a ground connection as you can see by the black wiring runing through everywhere. And then some wires from the input jacks to the potmeters. Then I started attaching all the wiring to the PCB. As you can see there is quite some wires actually. It was quite a challenge to organize them a bit also because they come from everywhere on the PCB. I also managed to solder on a screw terminal for the power like I did for my Yusynth modules. The only thing that annoys be a bit is that the elco's on the bottom are not all straight on. But this was quite a tight fit. Ah well nobody will see it eventually, but I like to have things neat and tidy.

And here is the finished module from the back. It is not always easy to solder the wires on the bottom layer of the dual stereo potmeters. The soldering lugs are quite difficult to reach sometimes. But I managed to get everything in place. Ray has quite a nice wiring scheme on his website that I followed. Sometimes the naming of the inputs and outputs on the PCB are a bit confusing. Well there is quite some as well as you can see. Well I think I managed to organize the wiring quite OK. Actually I didn't even expect that up front ;)

And here is a shot of the front of the module. I seem to have made a little mistake somewhere with the design. I had to adjust the 4 pot bracket I used because the potmeters where not all in the perfect spot. But I don't see it from this shot do you? Looks alright to me, but then again I don't really have an eye for these sort of things. If you like to use this front panel design, just send me an E-mal and I'll give you the .fpd file for Front Panel Express. OK now it is time for some testing. I will do that tonight after dinner. For now I'm going to take a little break :)

Wilba MB-6582 (Part 2)

Last week I started on the front panel PCB for the Wilba MB-6582 SID synthesizer. As you can see this is also a very professional looking PCB. It will fit directly behind the front panel itself and holds all the front panel components. First thing to do is solder 50 1N4148 diodes on this PCB. Quite some work and of course you have to watch carefully that you don't make mistakes with the orientation of the diodes. The reason you have to do these diodes first is that you can lay the pcb on its back and it will press the diodes down so that they don't fall out while soldering.

After that the rest of the front panel components can be mounted. There are 15 rotary controllers on there. They look like potmeters but are actually digital in stead of analog. They also have no beginning and no end. So they are called continues. I also mounted 48 ALPS tactile switches. All these components must be tightly fitted because they need to stick through the front panel later on. The last thing to do on this PCB is to mount about 128 3mm leds. They also need to be perfectly aligned. I think this will become a challenge, because they need to stick out a bit to go through the front panel.

In the mean time I also got the PT-10 case for the synthesizer. I got mine from Mouser in the US. It is actually the same case that Elby used on the AVR32 Synth I recently build. But this will look a lot neater I guess later on because of the cool front panel. The panels also arrived already. In the picture on the left you can see that the back panel is mounted in the case already. There is a DB25 connector on there that is not really necessary, but you can use it to make external connections for you own use.


And here is a picture from the back of the synthesizer. There is a 40 mm fan installed as you can see. Wilba states though about this fan that it isn't really nessecary, but some airflow will help the power regulators to dissipate their heat. And he also states it looks cool ;) Well he is right about that. Further more there is the power connector for the C64 power supply, two midi connectors and the 4 stereo output jacks. I need to find out what the other holes are for. I didn't look into that. But it already looks quite neat doesn't it? But wait until you see the front panel :)

Looks great doesn't it? The rectangular hole on top is for display. I got mine in the mean time as well. I can't wait to hook it up. But first things first. This front panel is also made by Schaeffer like the MOTM style front panels I made for my big modular setup. As you can see they can also do colors :) I didn't know that actually. On the top left the will be a matrix of 64 leds :) This will be a serious piece of eye candy when it is done. I just hope that it will sound as good as it looks. Now I need to find a C64 power supply. If you have one left you want to get rid of let me know ;)

Mr. Braska's Apollo Studio Experience (Part 4)

Today I showed Mr. Braska a bit more around in my studio. Here is Mr. Braska with the Elektor Formant that I'm repairing. He liked it a lot.

Then I showed mr. Braska my first modular DIY project. The PAIA 9700S Analog Modular Synthesizer. I build that long time ago already.

Then I showed him another project that I'm currently working on. This will become a MFOS 16 step sequencer. Mr. Braska was really pleased with all the leds :)

Then I told Mr. Braska that we had to stop the tour for today, because my furniture builder Gerrit was coming today to make some adjustments to my modular desk.

I explained that my Synthesizers.com Q960 sequencers didn't fit and we had to remove some pieces of wood to get them in. Mr. Braska started investigating this from the inside and confirmed that we were right.

And with this picture Mr. Braska has again reveiled a bit more of my modular desk :) Next time the Q960's will be in place and we will present the whole desk to you.

MFOS VC-LFO New Front Panel

I bought a Music From Outer Space (MFOS) Voltage Controlled Low Frequency Oscillator (VC-LFO) a while ago from E-bay. When it arrived it didn't work properly and I succesfully repaired it back then, but I wasn't happy with the build quality either and the fact that it had a front panel that read Oakley VCO. So I decided to buy a new front panel for and and completely rebuild it. Here you see the old unit. As you can see the PCB is fastened with a piece of plastic on top, but it isn't really secure. It fell out a couple of times and after the last time I was fed up with that as well.

The first thing I did was remove all the old wiring from the PCB. After that I used a desolder pump to remove the solder from the PCB holes. And then I put new wiring on the PCB. I got a new front panel from Bridechamber, but there is something I didn't really get. The PCB has a potmeter for Course Tuning and Fine Tuning, but on the front panel only Course. And there is a Sine Shaper potmeter on the front panel that I didn't understand. Eventually I decided to use the Sine Shaper potmeter for the Fine Tuning. I also used a 3 pot bracket from Bridechamber to fasten the PCB.

And here is a picture of the finished module. The only thing I left in place is the wiring for the power. There is also already a MOTM style power connector on there. Something I still need to do for my other units. After this I looked again at the signals coming from this unit. And I was a bit surprised. Even though I didn't change anything the signals didn't all look that great. But there is not much calibrating that you can do on this unit. I think I'll go and see if all the correct components are used on the PCB. I can't imagine it is supposed to work like this.

And here is the finished module on the right. It has two potmeters for CV inputs now and also an input with potmeter for the Pulse Width Modulation. And then there are 5 simultaneous outputs with Sine Wave, Triangle, Saw, Ramp and Square. Right of the module you can still see the old front panel. I already have two Oakley VC-LFO PCB's as well in the mean time. But I'm not sure that I'm going to use this front panel. Ah well we'll see :) Today I looked a bit through my backlog of PCB's while searching for the Oakley VC-LFO. And I found some PCB's that I didn't even know I had :) Hmmmm.. Still lots of work to do. But let's first finish up the modules that are already done. I'll keep you updated on the progress as usual. Enough for now.

Yusynth (Part 22)

This evening I started calibrating and tuning the Yusynth VCO I build today. The calibration part consists of two parts. First you have to center the Saw wave around the zero Volts with a 25 Turn trim potmeter and prevent it from clipping either on the positive or negative part. You can only do this with an oscilloscope. Then you have to fine tune the shape of the Sine wave and Triangle wave with another trim potmeter. Again you can only do this with an oscilloscope. You can see what it looks like in the picture. This part is quite easy actually and I have done it before with LFO's.

The tuning part is a lot more complicated. First you need a trusted CV source. You could use a tested and tuned midi to CV interface for example, but I decided to use the CV keyboard from my Roland System 100m set. The only problem with that one is that there is a tune button on that as well. So I used a Volt meter first to make sure that its output was exactly 1V/Oct and I was quite confident that it was. Then I attached a frequency counter to meeasure the exact frequencies on the output. The calibration proces is very well explained on Yves website by the way.

Here you can see my test setup. On top in the middle is the Volt meter. You can see it reads 4.00 Volts and the frequency counter measures 440.1857 Hz. Then you drop an octave and the Volt meter should read 3.00 Volts then and the frequency should be half so 220 Hz. While doing this you change the V/Oct trim potmeter until it is correct. Then you repeat this over and over again until it is in tune over an octave or 5. That should be fine I guess. I also send the output to a pair of speakers so that I could tune a bit on hearing as well.

Here is another shot with 2.001 Volts on the CV input (close enough for me) and 109.9316 Hz in stead of 110. Well I've seen a lot of number like this. After about an hour or two fiddling around like this I was finally satisfied. Actually I don't even know if my frequency counter is that good. But it sounded quite OK :) I run it through some sound effects and played some melodies on the VCO. Well I'm quite happy with that sound and also how it tracks. So Yves did a very good job with this design. And I already decided that I'm going to build some more of his VCO's :) I can recommend it. You will have a very good oscillator for a very low price. And it doesn't get more analog :)

Mr. Braska's Apollo Studio Experience (Part 3)

Here is the third part already of the mr. Braska Apollo Studio tour. Here you see a familiar sight to start with. Mr. Braska wanted to sit on top of this Yusynth Mixer module as well.

Then Mr. Braska said he would wire the Yusynth VCO module for me. Hmmmm.. Well look what happened. I don't think he is getting this done on his own. I think I will help him a bit ;)

And here is Mr. Baska applauding at the result of the final VCO. He didn't think it would ever happen anymore after his dissapointing experience.

After that we ran the finished VCO module through a Murf Moogerfrooger. Mr. Braska really loved that. Here you see him changing patterns on the Murf.

And to conclude this post mr. Braska reveals a bit more of my modular setup as promised. Not all of these modules are done yet. But they will be very soon.