Modular Progress Overview 3

I promised to make a new overview picture of the modular that I'm building. As you can see the center cabinet is almost filled up, but not everything in there is ready yet. Only the modules with all knobs on are done and tested. On the left extension there is still space for some MOTM style modules. I will build some more drum modules that will go in there. And on the right there is more room for 19 inch stuff. I'm still waiting for a power supply from MOTM and some power distribution boards. So not everything is powered yet. But when that stuff arrives that will be the first job I'm going to do. But for now I'm still working on finishing up a lot of modules that are halfway done or so. I think I'm also halfway the whole project now. So this picture is a nice landmark I guess for that :) You can click the picture by the way for a bigger version.

Modular Progress Overview 2

I'm working very hard now on finishing some modules for my big modular. So I thought it was a nice moment to post another overview of the current status. I know some of you are following this blog for my DIY stuff and some of you have no idea what it is all about :) So from time to time I will show what it is becoming. In the picture on the left are the modules that I have finished or nearly finished. I'm working at the moment on the YuSynth LFO's and Saw Animator. So you can expect a post on those soon. If you click on the picture and zoom in you can see what it all is. Every module has a text label.

And here is the big overview picture of the hole modular desk. As you can see there is still a lot of empty space, but that will become all filled some time to form one big modular synthesizer. Most stuff will be self build, but there will also be some pre-build modules in there soon like the Synthesizers.com modules I bought recently. On the top left you see the ASM-2 that I'm also still building and in the middle on top is the Elektor Formant that I still need to restore as well. I tried to repair the old power supply that came with it, but it is so damaged that I decided to go for a new power supply for it actually.

And there is lot to some soon. I have been working on a lot of modules the last year that all are missing parts. 95% of the components on the PCB's is very ordinary and cheap stuff that I can find in my local electronics shop, but some parts are very difficult to track down and sometimes quite expensive. So I have a huge backlog of stuff I need to finish right now. I will do a post about that as well later on so you have an idea. I'm still enjoying especially the DIY stuff a lot, but the whole modular is still not in any state to produce music with it. So I'm really eager to create some sounds with it soon, that is why I'm working very hard now to finish enough stuff to be able to hook it all up soon :)

Formant (Part 3)

After the first initial study of the Elektor Formant setup I bought. I decided to completely rewire it. In the picture on the left you see the backside of the Formant completely stripped now. The main reason for doing this is that I didn't like the kind of wire that was used in some places (flat cable) and inconsistent use of colors of the wires. I hate that. Especially because two power buses run through each other One being +15 and -15 Volts and the other being +5 Volts. You don't want to mix them up by accident. For the audio signals coax cable was used. I think that was a wise choice, but I will renew that as well because I want to change the functionality of the modular. Make it less prepatched. I looked more like a semi-modular now.

In the picture on the right you see what came out. It is not even that much wiring, but it did take me about an hour to neatly remove it without doing damage to the card edge connectors on the back of the modules. The coming week I'll pick up some roles of new wire in different colors. I will need that anyway for my ASM-2 and Yusynth projects. I want to use the same colors there so I won't make mistakes easily. Better safe than sorry I guess. I'll also have to pick up some mini jack chassis parts to add some extra patch points on the front panels.

The next thing I did is take the power supply out for closer inspection. I noticed immediately that one of the fuses was blown and after measuring the other two I found that both the +15 and -15 Volt fuses were broken. They are the 2 Amp slow type. I didn't have them in stock so I'll have to pick them up as well and see what happens when I put in new ones. I'll get some extra ones because I don't know what made them break. Could be a short circuit in the wiring, or a broken module or the power supply itself. This is another reason why I wanted to take out the wiring. I will use the short circuit protected lab power supply I bought recently to test the modules one by one.

I also had a look at the bottom of the power supply PCB. Not the best soldering I have ever seen but it looked quite OK for such an old project. I did resolder some joints that looked a bit weird. I also removed the wires that were still attached to it. I was amazed that multiple power take off points are available on the PCB that were not used at all. I think it is better to bring the power to the seperate places from a star topology than to make one long bus that the original builder of this project did.

The Power components I found on the heat sink that was loose in the cabinet belong to the power supply. That is the three 2N3055's power transistors that are on there. There is also one 2N5558 on there. I have no idea yet what that one is for. On the PCB there are clear points were to hook up the 2N3055 neatly marked with E, B, C for Emitter, Base and Collector. The power transistors seem to be in order at first sight, but I did measure them yet.

On the bottom of the heat sink the Emitter and Base are also neatly marked with a pencil. And the base is unmarked but there are extra nuts attached to the neatly insulated housing so I know where they should go. I also took the transformer out of the Formant case. I can rebuild the power circuit now and test it separately. Always an exciting job because you never know if something is going to blow in a power supply with 2 broken fuses. Well I'll update you on that soon.

Again Some Studio Changes

Today I cleaned up the studio a bit. It got a bit messy from all the electronics projects I did in there. I also moved around some stuff again. I'm still finding the best spot for all my gear. I found a nice place for the Formant in my analog corner. It is on the floor with the keyboard on top. This way I can move it around easily to work on it and can also play the keyboard. I did some more work on the Formant this morning as well. I will tell about that in the Formant Series part 3 that I'm going to post later. My analog corner is getting quite crowded now. I'm happy that we are going to start building the Apollo studio soon, so that I will have a bit more room again.

Another thing I did is swap the Oberheim OB12 for the Roland JP-8000. I love to play leads on the JP-8000. I like how the keyboard plays and also the sound is very good. I'm going to use the JP8000 for some leads in songs I'm working on right now. It is very analog in look, feel and sound actually. I put in in my digital corner right behind me. I have got some kind of a 'U' setup now there with keyboards on the left of me, in front of me and right to me. Very nice when jamming late at night. I agreed with my friend Chriz that we are going to make new studio pictures soon and also new movies for the website, because so many things have moved around since the last time we did that. I'll update you on that of course.

Formant (Part 2)

Yesterday evening I picked up the Formant from the seller. I stayed there a lot longer than anticipated but we had a nice musician to musician talk about a lot of things. It is always nice to also meet new people while buying new gear from them. The setup was a bit smaller in size than I expected which was a nice surprise. Here you see the Formant keyboard on top of the setup. I think from the size of the 3 octave keyboard you can estimate the width of the setup. The first thing I did is study a bit how all the cabling was hooked up. There was a lot more pre-patched than I expected. I guess I will change that a bit since I want to hook it up also to my other modulars later.

When I studied it closer I was surprised about the fact that the PCB's of the modules were not fixed to the front panels. A lot different than the Yusynth modules I'm working on. There is a whole metal construction in the wooden case to hold the modules. Also the whole inside of the case is covered with tin foil. This is done for shielding purposes I guess. Another thing I was a bit surprised about is the stuff that was laying around loose in it. From the loose components and the wooden housing I could tell that there used to be a back panel, but that is missing now. It was probably ripped of by force and took a lot of components with it.

In the picture on the left you see the power supply that is fixed to the bottom of the casing. It is the original Formant power supply which is nice. In front of it you see a rather big heat sink with power components attached. I guess this was somehow connected to the back panel once. I will take the power supply out soon for closer inspection and try to get it working again. I didn't try it on yet because I didn't want to blow the fuse in my house ;) I think it is wise to study it a bit more first. I'm quite sure it won't work.


Another thing I found lying around is the receiver module for the keyboard. This gives power to the keyboard and outputes the Voltage Control and Gate signals to the modules. I will incorporate this one again but I will also build in a Midi2CV module for the Formant so I can hook it up to my midi setup. All in all the Formant was in a bit worse shape than I had hoped for. I'm going to study some more on the schematics and documentation and than decide from there on were to go. I'll keep you posted on this project as usual.

Formant (Part 1)

I have been planning to build a Formant modular for a long time as well. I found all the documentation on the Internet and was already reading myself into this material. But I also saw that building these projects take a lot of time take keeps me from producing music. So I looked several times to buy a used set. But most of the times they just didn't fit my needs. Until very recently. I found a very nice set on a Dutch website. They guy that sells it even lived very close to me. At first I started bidding, but later I just mailed him what he asked for it and decided to go for it. I will pick it up on Monday if all goes well.

As you can see it is a very nice set. I has four VCO's, two normal VCF's and also two 24 dB VCF's, two dual VCA's, one noise module, a RFM module (some kind of equalizing module), two LFO's, a COM module (output) and seven ADSR envelope generators! So a lot of modules. I heard the sound of the Formant before and it is really nice. It is also very old by the way. The original design was printed as a DIY project in the Elektor magazine of May 1977! I'm not sure though when this one was actually build. The current owner didn't build it himself either.

I also like the fact that the keyboard is also included in this set. You can see the keyboard in the picture on the left on top of the modules. I was especially not looking forward to building this one my self. Another thing is that I like the fact that the orginal front panels and knobs are used on this one. But why did I buy this when I like DIY so much? Well it is not in perfect order. A lot of the wiring is broken I understood. I'll see monday though in what state it is. So this will be some kind of a restauration project.

You can see some of the broken wiring in the picture on the left. I will probably completely redo this. And after that see what else is in need of fixing. Well I have all the schematics and most modules are present more than once for comparison. So I think it will be doable. I got this pictures by the way from the current owner. I hope he doens't mind that I used them here. I can't want until Monday to hear this synthesizer in action. I'm also thinking of maybe building some more modules in the future, but I can off course also hook it up to the other projects I'm working on. That is the fun of modulars :D