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.

ASM-2 (Part 10)

I worked some more on the ASM-2 last week. I did some more work on the front panel components. This time I installed a lot of pot meters. The hardest thing is to figure out what goes where. There is no clear documentation on this only some suggestions from Elby Designs. I ordered a complete front panel component kit back then, but it looks like it isn't complete. I'm definitely some pot meters short and I found a broken one in the package. I also installed two push button switches for manual gating the ADSR's and three rotary switches that had to be limited to 4 positions first. Finally I installed some led holders where I changed the leds in some because I wanted different colors than were in there. I also switched the stereo jacks I had left from the last time.

And here is a picture of the back of the front panel. You can see there are still some components missing. Those are not all the missing pot meters. I still have some left, but not enough. What is also strange is that in the front panel the holes for the potmeters or VCA2 are bigger than on VCA1. I guess that is a design flaw, I can't imagine any reason why there should be different size potmeters there. I will e-mail Elby with these questions before I continue. It is nice to know what you are doing I guess :) And to be honest I'm done with it for now as well. This is not the job I like the most. Because the cabinet is so big it is quite difficult to hold a component on the front and fasten it from the back. I can feel some muscles now that I didn't know I had ;)

So after this I put the ASM-2 cabinet back on top of my modular desk. I still think it looks great there. But for now it is not doing anything but standing there. I hope I can get some life into it soon, but I still have a lot of other projects that I need to finish also that I think are more important first. Next week Gerrit my furniture builder is coming with the second extension to the modular desk by the way. I already let him know that some modifications must be made to the first extension. Most modules don't fit in there unfortunately. Ah well. We'll get that right eventually as well.

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 :)

ASM-2 (Part 9)

This evening after dinner I started to test the ASM-2 main PCB. I started with measuring the power. There is a +15/-15 Volt power rail and that seemed to work quite well. Besides there are some +10/-10 Volt reference points on the PCB to use for calibrating purposes. They all looked fine to me. The power regulators got a bit warm, but not hot, so I guess the PSU is holding fine. I hooked up a connector to the common power rail to get a ground for my oscilloscope to be able to look at some signals.

I started by testing the oscillator outputs. On VCO-2 everything looked very nice. I just had to calibrate some of the wave shapers to get symmetric waveforms, but on VCO-1 I found something strange. The sawtooth looked fine and also the square wave, but the sine wave and triangle were completely screwed up. In the picture on the right you see the waveform I got from the triangle wave. This looks more like a distorted saw actually. It clips on +15 and -15 Volt as well and it was supposed to be 10 Volts peak to peak. So time for some trouble shooting.

I started to study the schematics of the oscillator and found quickly that the base waveform is the saw and the other waves are generated from that one. The sine wave is generated from the triangle, so the problem had to be in the wave shaper circuit for the triangle wave. It is based on two diodes and a TL084. After a measuring and comparing to the other VCO I found that on one of the outputs of the TL084 I got no output signal. At first I thought the TL084 was broken, but when I wanted to swap it I felt it was warm. I looked under the PCB and found the problem. A tiny drop of solder was between the output of this IC and a through hole on the PCB. It was so tiny that I missed it on the two earlier inspections I did. But I could measure it.

After I removed it this was the result. On the picture on the right you see a very nice triangle wave. And after this also the sine wave was fine. When I tell it like this it sounds like this was an hour work, but actually it took me the whole evening to find this. But afterwards it is always a gratifying feeling when you solved a problem like this. The next thing is to calibrate the VCO's and test the rest of the modules. I hope that goes a bit smoother. At the moment I'm checking how to hook up everything, but I think I need some more crocodile clamped wires.

ASM-2 (Part 8)

Last week when I had to stop soldering because it was leaking again, I decided to pick up another job. I took the ASM-2 cabinet down from my modular desk and started to mount the jack connectors to the front panel. There are a lot of them I can tell you. It took me a while before I found an effective method to fasten them and get them straight at the same time. Another thing that puzzled me is that I had 4 stereo jacks and the rest was mono. So I E-mailed Laurie from Elby Designs about this and he got back to me on this.

One turned out to be for the AVRSynth32 actually and I know where to put the other three now. Here you see the whole thing from the back. All the jacks are switchable in order to be able to make the ASM-2 semi-modular. If you look closely at the front panel you can see that besides all the input jacks there is also written where it gets its normalized input from. It took me a while to figure this out by the way. But now I understand it and it makes perfect sense. In the picture you can also see that I can easily take the back of because it is fastened with some magnets.

There are still lots more front panel components left to mount. After the jacks I started sorting and counting the pot meters. And there I also found the 8 missing pot meters for the AVRSynth32. So that problem is solved as well now. Most potmeters are 100K linear, but there are some other ones as well. I'm going to focus first on finding out where they should go. Besides that of course a lot of knobs, and some turn switches, leds, and switches. I'm still struggling a lot with the documentation of the ASM-2, but I'm sure that in time I will understand it all.

After I sorted all the components I decided I did enough mounting of front panel components and looked the PCB's up again from my stack of unfinished electronics. The first thing I had to do was to mount two heat sinks on the power regulators. I got them long time ago from Elby Designs but just didn't mount them yet. After that I started to read again through the documentation to see what power I should apply in able to start testing the PCB's. It turned out that the main PCB needed +24 and -24 Volts. So I put my lab power supply to this and did the famous smoke test. Well no smoke :) So all is set to start testing this PCB. I hope everything works because error seeking will be a pain in the ass on this one :)

Modular DIY Preparation

After my album is released on the 17th I'll be continuing to finish my studio (yes I still have work to do) and I'll will start working on my DIY modular project again. I'm really looking forward to that, since I did a lot of stuff already but when I was just about to test some stuff the work on constructing the studio started and when that was finished I had to start on my album. So it has been a long time ago since I worked on that project. One of the things I noticed is that I didn't have enough light on my modular desk to solder properly so I bought this new lamp. It is a TL so it gives bright white light and I can adjust it to be just over my workspace. Also there is a magnifying glass on it to see what I'm doing when I have to do really small stuff.

I also ordered some stuff the last months that I also need for the big modular project. To start with I bought two power supply kits from MOTM. One has only +12V and -12V and the other one has +12V, -12V and also +5V. Some modules need this. I also ordered some power distribution boards for inside the cabinet. This way it is easy to get the power everywhere I need it. I thought there was more work to be done on the power supply kits, but it looks like it is only wiring it to the frontpanel components and fitting it on there.

In the picture on the left you can see the front panels that came with it. Just a switch and a power connector on there actually. I probably will need one or two more power supplies later on to power the whole modular, but for now I have enough to start with and I also still have the lab power supplies that I can use in addition. I'll start by testing the modular on the lab power supplies anyway since they are short circuit proof ;) Just in case something is wrong with the electronics I build. I just have to figure out a neat way to get power to the front of the units.

I also bought some other stuff. Here you see some new PCB's. I'm planning to build a MFOS sequencer and also a Klee sequencer from Electro-music.com. For the Klee sequencer I also got a front panel from Bride Chamber and hopefully they will have a front panel soon for the MFOS sequencer. From Elby Designs I ordered the front panel components for the ASM-2 I'm building. So I don't think I have to be bored the coming period :) Of course I'll update you with nice pictures (and hopefully some sounds) during the construction of all this nice equipment. As said before I can't wait to start working again on this. And hopefully relax a but during the process. I really need it!

ASM-2 (Part 7)

It has been a while since I worked on my DIY projects with the deadline stress for the album, but I picked up now where I left. I want to try and finish the ASM-2 first. In the picture on the left you can see the completely finished PolyDAC PCB. I also finished the Raw DC PCB by now. Not very exciting to look at. Basically it is just a rough power converter from AC to DC. It is nice that is a separate PCB so it can be mounted in the cabinet somewhere far away together with a transformer to avoid it from interfering the audio signal.

I also received the front panel for the ASM-2 recently. It was actually way bigger than I expected. From the pictures on the website from Elby I figured it would be 19'' format. But you can see it standing against our couch here so I can guess you can judge the format from it. If not there are some more pictures later on in the post. I also ordered all the knobs from Elby Designs. All I have to do now is find suitable front panel components like potmeters, switches, jacks etc. I will try to find them from my local electronics shop. Elby was very nice to provide a list with all the components they use themselves so I can try to find matching components here.

Since I'm talking a lot to the guy that is going to build my studio furniture, we also talked about modulars. We even agreed to make a very special desk for my electronics/modular corner that will include the Yusynth modular I'm going to build. I'm very excited about that. It will be great for sure. But I also asked him if he maybe could make a cabinet in the same style of wood for the ASM-2 and he agreed that was a good idea :) So I gave him the front panel and he started working on it right away.

As you can see it looks great already :) But he said it needed another two layers of coating. And he was constructing some metal strips to go on the edges since I mentioned to him that I wanted to be able to take this synthesizer along to synth meetings, since I think it will become something very special. It will be put on top of the YuSynth studio furniture that he will build for me and as far as my imagination goes that will look spectacular later on :) I'll keep you posted on this for sure.

ASM-2 (Part 6)

Today I did the construction of the PolyDAC Midi2CV converter PCB. As I said in the last post I ordered the complete kit from Elby Designs inclusive all the necessary components. After checking all the parts I found out that I had one resistor too much and came a 78L05 short. I will contact Elby to ship it with my next order. You can see the checklists that come with it wich are very handy. It also says which part number is which value. So it is perfect to take as a guidline for contruction.

My oldest daughter Joyce helped my out again today. She is 7 years old and really fond of electronics. Last week when the new parts arrived from Elby she was very excited and asked me a couple of times to wait with soldering so she could help. She usually looks up the part numbers on the PCB or in this case on the silk screen print out Elby supplied. This way she could look up the next part while is was soldering the one she looked up before. After that she points out the location to me for the next one. It really saves me time :) She also loves computer games so I guess she'll grow up to be a computer/electronics nerd just like daddy ;)

It is so relaxed to have the silk screen again for component orientation and I don't have to worry about misfitting. Despite that I did put one resistor in the wrong place. I had to take it out with the desoldering pump. That went reasonably smooth. Further I found it to be a very easy PCB. I was only doubting a bit about the orientation of the Crystal. But I think it should be mounted correctly now. There was one opto coupler supplied that was another type than stated on the documentation, but I found on the internet this was a perfect replacement with even the same specifications so that should also be OK .

In the picture on the right you see the finished PCB. There are only some connectors missing to connect the front panel components later. They were not included in the kit I ordered. But these are exactly the same as on the ASM-2 PCB. So I can get those at my local electronics shop too. All in all a nice way to spend the Sunday afternoon. Next thing is to look at a power supply for the project and order the front panel from Elby Designs. But before that I'll probably try to test this PCB because my friend Hanz is interested in one as well for his modular. If this one works OK I'll probably build another one for him. More on the ASM-2 project later.

ASM-2 (Part 5)

I haven't posted much progress on the ASM-2 project. That is because I had some trouble finding two very simple 120 nF capacitors. Well I got a very spontaneous E-mail from very nice guy from the US offering me to order them for me at his supplier. Don't you just love the Internet for that? He even ordered two different kinds so I could choose. And he didn't even want anything for it. So I sent him a copy of my CD to thank him. And on the left you see the type I chose. They fitted perfectly. (LB thank you again!!)

I also had trouble finding the right heat sinks for the power regulators. Elby made some mounting holes in the PCB so they are more fixed and not all the weight are on the leads of the power regulators. Eventually I decided to ask Elby Designs to send them along with an order I placed for more stuff. I mailed this after the order was already payed and told them to let me know what the costs would be, but they even included them for free! Great service! Not I have everything for the ASM-2 PCB. I only need to find me two M3 bolts and nuts to fasten the heat sinks to the power regulators. I'll probably have some laying around somewhere.

So what did I order from Elby? Well the ASM-2 PCB is not the only PCB that is needed. The ASM-2 Wizard design also includes a PolyDAC. This is a 4 Channel Midi to CV converter. After this I will also have to make a power supply. This PCB is rather simple though. So I'm even considering to make it myself, but I'm not sure about that yet. As you can see this PCB is double sided and has a silk screen again. So luxurious soldering again :)

I also ordered the complete component kit. I was getting a bit tired of finding the right components every time. So yes I'm a bit lazy on this project. In the picture on the right you see the complete kit. All the components are conviently bagged and tagged. So you don't even have to search. Very nicely done by Elby designs.

I'm looking forward to build this PolyDAC and my daughter as well. She loves to look up the component numbers on the PCB. So I let her do that. She already wanted to start on it yesterday, but I needed to do some other stuff first. But probably tomorrow we will begin on the contruction of this PCB. I'll update you when it is done :)

I can hear you thinking now: 'You must have a pile of PCB's by now?'. Uhh yes as a matter of fact I do. You can see it in the picture on the left. There is even a larger PCB on the bottom ;) A future project I'll let you guess at for now. But don't worry I'm going to finish all these projects. I just have very chaotic way of doing everything at the same time. I need that I guess to keep inspired. But I always finish what I start. It will just take some time before it is all done.

ASM-2 (Part 4)

Yesterday I received another bunch of parts for my ASM-2. With this parts I finished the PCB. I only miss two 120 nF capacitors. The strange thing is that no manufacturer has those values anymore in their assortment. I will ask Elby Designs if they can supply them or maybe I can replace them with 100 nF or 150 nF. I don't know how critical the value is. Two other components are not fitted yet. The power regulators. I already have them, but the heat sinks that I got are not the right ones. So I'm going to look a bit further. The probably will work, but on the PCB are some mounting holes. The ones I got will be screwed onto the regulators but don't rest on the PCB. This means a lot of stress on the leads of the regulators. I'm afraid they will break from the weight of the heat sinks.

On the right you see another picture of my PCB from another angle. On the bottom you see a nice picture that is on the website of Elby Designs. I used this one to check the result of my own PCB as well. On this picture below you see the heat sinks attached to the PCB. This looks very solid. The next thing to do is to start working on the front panel. I still need to order it as well as all the jack connectors and the pot meters with knobs , but I have been just too busy so far. So far it has been fun building this unit, but I'm still far from getting some sounds from it. Well patience is a virtue they say. I don't have much of that though ;) As you can see below my work looks quite OK. Even still it will be an exciting moment when I connect power to the PCB.

I hope Elby Dedigns doesn't mind me using this picture on my blog, but it is a way better picture than I could take. In the end I'm promoting their project so probably they wont mind :) I'm not such a good photographer and wanted to give you a good idea how it looks like ;) When you click the image you can see it up close. You will notice that some components are not installed. This is intentional. Some components are optional, so you have some choices on the functionality while building. When I continue I will update you off course.

ASM-2 (Part 3)

A little update on the progress on the ASM-2. I nearly finished mounting the components on the PCB that I got so far. I got some wrong components from the local electronics shop though, so this morning I went there to trade some stuff. I turns out that they couldn't deliver all the parts and they supplied me with some replacements for some parts. But not all off them meet the desired types and tolerances. Some they say they just can't get. So I will have to see if I can get them from somewhere else or maybe from Elby Designs.

I also got all the connectors that will connect the frontpanel components to the PCB. The connectors are pre-wired as you can see. Probably the wires are too short, but it is quite easy to extend the wires. That is easier anyway than soldering the wires to the little pins of the connectors. This reminds me that I need to order more stuff from Elby Designs. They sell a ready to go frontpanel that looks really great and a complete kit with all the frontpanel components like potmeters, jacks, switches and leds. It is a bit more expensive when I order from them I guess but them I'm sure that I will get the right stuff and everything at the same time. I also need to construct a power supply and a midi2CV converter were they also sell PCB's for.

On the left you see all the components I picked up this morning that I need to mount to the PCB now. I got some of the polystyrene capacitors that turned out they had anyway, but unfortunately not all the values. I also changed the trimpotmeters since the pin layout on the ones I got was wrong. I got one missing LM1497, but one TL081 is still missing. I got BC550's in stead of the BC549 that were in the pick lists. They said that the BC550 is the follow up for the BC549. I'll try that ou. For the 7915 and 7815 power regulators we found two heat sinks. I hope they will fit. They ordered the rest they could get for me. I hope to get these next week. All in all it looks like a bit more work to get the component especially compared to the complete PAIA kits. Construction so far is quite easy. But before I have a fully functional synthesizer will take a while I guess.

ASM-2 (Part 2)

Today I also started working on the ASM-2. Most of the components arrived. You can see the stack of components in the picture on the left. Yes this will actually become a synthesizer :) Sorting out all the components was the first task and checking if I had everything. I knew some resistors were missing since they were in backorder. But probably I will find out along the way what I'm really missing. I put all the components in plastic bags, so I can't loose them. But from the amount of resistors only I know that this will be a lot of work to build.

I started soldering the first resistors today. First only the 100K and 10K resistors because these were the most. Actually my oldest daughter helped me to find the resistor numbers on the PCB. She really enjoyed helping me. Since all resistors are 1% tolerance reading color codes on the resistors is a pain in the ass. So I took my multi meter and actually measured the values on there. I expected that to be much more work than reading the codes, but I found out that this way is even faster. So something learned for the future :) On the right you can see how far I got today.

Not so far is seems and still I was busy for two hours. On the left you see all the components that are still left in the plastic bags. But I'm not complaining. Soldering is something that helps me relax. I'm very busy at work at the moment and this helps to get my mind clear, because I don't have time to think about anything else. I hope I can find time during the weekend to work on it some more. Off Course I will post an update here when I have accomplished something substantial. But I guess it will take a while before the whole PCB is finished. I will keep you posted :)

ASM-2 (Part 1)

My next DIY synthesizer project just arrived in the mail. Always nice to get such a package. I really got the taste now for soldering, so you will see lots more DIY projects in the future. The next synthesizer I'm going to build is called the ASM-2. It is an analog synthesizer concept from Elby Designs that you can build in two different ways. Either as a the 'Genie' version or the 'Wizard'. The Genie is a prewired version and the Wizard is a complete modular version. I chose for the modular design. This project differs a lot though from the PAIA projects I did. The documentation is a lot more complicated it even comes with some modifications right away on the original design. You can buy it as a complete kit at once. But you can chose to buy your own components from somewhere else or buy it in pieces.

I started out by ordering the PCB. The whole synthesizer is build on one PCB, but it is divided in modules. Like VCO's, VCF's etc. The PCB also comes with some papers that describe the modifications you should do right away and also a pick list for the components needed for the PCB. Also a CD-ROM is included with all the documentation you need to build the project. I looked trough all of it and I know I have quite a task in front of me. But life is supposed to be a challenge right? :) Well I really look forward to this one.

Another thing I ordered right away was the 'Special Components' kit. These are components that are difficult to get. So rare parts. The rest should be easier to get from a local electronics store. So that is what I'm going to do. I already gave them the pick list for all the resistors, capacitors etc. In the picture on the left you see the special components. Off course I will post all updates on this project in my blog. You can find more information on the ASM-2 on this URL: http://www.elby-designs.com/asm-2/asm2.htm