One set of MB-6582 knobs left!

A while ago I build a Wilba MB-6582 synthesizer kit. I was too late for a group buy and had to buy a full bag of knobs for myself. In the mean time I have sold a large part of the remaining knobs and today I'm sending away another set of them. I just counted my knobs and I still have one set left. So be quick if you need these knobs, they are hard to get by in small numbers. If you are interested just send me an E-mail and I'll make you a nice deal.

Wilba MB-6582 (Part 8)

When I recently took the pictures of the SammichSID's I build together with the Wilba MB-6582 I realized there was still one more thing to do. There were still no knobs on the unit making it look like a work in progress even though it is finished and works fine. So I looked again for some knobs on the Internet. The company that makes them doesn't sell very small amounts and you only need 15 for the unit. I could not find another place to buy them so I decided to order 100 of them.

Today they arrived and I put them on immediately. And well I think they look stunning. Wilba really made a good choice with these knobs. Not the MB-6582 finally looks like a finished project :) I'm still considering though to change some or all of the SID chips for newer ones. I now have 8 of the vintage sounding 6581's in them. But I liked the sound of the newer 6582 or 8580 better to be honest. But I guess it won't be easy to find them. And I'm not even sure what I want. It both has something special so maybe I should put in 4 new ones and leave 4 old ones.

Back to the knobs. As you can see I still have a lot left and I would not know where I could use them elsewhere. So if you are building a Wilba MB-6582  kit or you are planning too, you could buy the 15 knobs from me. You could pay me with PayPal and I'd ship them to you. Just send me an E-mail if you are interested. I won't throw them away of course and it would be nice if I could help someone out this way. I guess I should put this information on the Midibox forum as well. OK enough about the knobs :)

Wilba MB-6582 (Part 7)

When I test the Wilba MB-6582 SID synthesizer something strange happened. It looked like two scan lines where stuck and SID 4 suddenly didn't work anymore. But this was not right away after the display was installed. It was actually the next day that this happened. I was a bit puzzled about it. But when I disconnected the display all worked fine again. So I suspected the display still had to touch some leads on the PCB. When I inspected the tape I saw that it was punctured already. I decided to mount some rings under the display to give it some more distance and that helped. Now it works perfectly. Ah well luckily I didn't have to remove either the front panel or the PCB behind it to do this.

In my previous post I promised to tell a bit more on the software installation. You need to install a tool on your PC called MIOS studio. You can get it from here: http://www.ucapps.de/mios_download.html this communicates over Midi with the PIC's on the PCB. All PIC's are connected to 'midi in' by default but on the PCB are some jumpers where you can decide which PIC is connected to 'midi out' to be able to communicate and you also have to select the correct Device ID in the software. 0 for PIC1, 1 for PIC2, 2 for PIC3 and 3 for PIC4. Then you have to load the Midibox SID V2 hex file into all four PIC's for the synthesizer to start working. You can download this from the same URL. It is not difficult at all, but it took me some time to figure out :)

And here is a picture of the finished MB-6582 including the Commodore power supply. The only thing I have left to do is source some nice knobs for the rotary encoders. This was really a nice project to build. I would not recommend this though if you are an absolute beginner. There are some more difficult tasks in the process. But the end result is worth it. I think it looks great, it is a very functional synthesizer with a very unique sound. It has quite some power as well. I'm already looking at some more midibox projects by the way. It is a great platform with a lot of nice stuff in the mean time to build. Like the V4 sequencer. My hands are itching for that one.

But first it was time to have some fun with the synthesizer. I uploaded the preset bank that is available with the MIOS studio installation and I must say some sounds really blew me away :) There are some great lead and bass sounds possible with this synthesizer. It is also nice that some sounds are actually polyphonic. And there is also a little sequencer build in, but I haven't been able to find it in the menu's yet. I guess like always I need to read the manual ;) Ah well. After I was done my youngest daughter also had a go with it and she was also pleased with it.

Wilba MB-6582 (Part 6)

Last night I worked some more on the Wilba MB-6582 SID Synthesizer. Here you can see a picture where I finally added all the flat cables. In total I made 8 and screwed up 5. The problem is especially with stripping the cable. Since it is very tough you easily apply to much force and also cut the wire. And since you have to to 16 strips on one cable, screwing up just one makes the cable unusable. In the end I improved my technique by partially cutting the insulation on both sides of a wire before pulling it of. In this way it takes less force and thus decreasing the possibility of an error.

After this the two PCB could be interconnected. This is also a challenge since you have to align 8 pins of a flat cable in the holes on the other PCB. The first few are OK since then you still have room to move, but since the flat cable is tough the final few are more difficult. It takes some patience :) Ah well it is done now and it looks fine I think. But I anticipated this to be about an hours work up front, but eventually it took me 4 hours in total. Ah but at least I learned from it ;) OK next thing up is attaching the display and front panel to the upper PCB.

And also that was a challenge. I didn't stick to the original building doc by the way. That suggests to glue the front panel to the casing, but I used the original screws to screw the PCB from the bottom. After this the screws sticked out and I just cut the surplus off. Then I could just lay the front panel on top and that is hold in place by the rings of the rotary controllers. The display is also fastened with 4 M2 nuts and bolts. I used some insulation tape to make sure the PCB of the display would not touch anything on the front panel PCB. This also took some more patience by the way ;) Aligning the front panel with all the little knobs ans leds is a painstaking task. But a well. Now it is done it looks great I think :)

And then the most interesting part. Testing! I switched the synthesizer on in the hope that some leds would light up, but actually nothing happened. You first have to load the software in there. So it is not plug and play at all. You can upload software to it via midi, so I attached it to the midi in and out of this Roland keyboard that is connected to the USB port of the PC on my modular desk. Then you have to download a special tool that can communicate with the PIC's on the main PCB. I first uploaded a led test program that switched on all the leds to see if they were not to bright. I didn't wait with installing the led resistors as I posted before, but it all looked fine. Not to bright at all. So that is more luck than wisdom actually. I"ll post about the rest of the software update procedure in a next post. So far at least it communicates with the PC :)

Wilba MB-6582 (Part 5)

I worked some more on the Wilba MB-6582 SID synthesizer. The first thing I did is making the cable for the LCD display. On the Wiki there is a link to an example for constructing this cable. My display had 16 pins just like the one in the example, but I decided to look up the specs heet to make sure the connections were the same and actually they were NOT!! So be careful when you are going to construct this yourself. Always look at the documentation of your display. I guess you can seriously damage your display when you hook it up in the wrong way.

Then it was time for some testing. I hooked up the LCD to the header connector of PIC1. Here you also have to look out carefully what pin 1 is. It is very easy to make a mistake here. When I applied power I saw nothing. The backlite lid up but no text, so I was a bit scared that I make a mistake after all. Then I remembered that there were some pot meters on the PCB to control the brightness and contrast of the LCD. And when I adjusted them a nice 'Ready' text showed up. After I booted again also the MIOS version showed while booting. So I guess this works alright. I seems though that the synthesizer doesn't hold the software it is supposed to run. I guess I'll have to upload some code to it, but I'll look at that later on.

The next thing to do is to connect both PCB's together. This is done by using some thicker flat cable. This stuff is very tough, so stripping is quite a task. But after screwing up two cables I found a good method for this. I think actually that this is the most challenging task in constructing the whole MB-6582 for me. I never used this cable and they all have to be the same length of course as well. Well I finished four of them and I still have four to go, but I was fed up with it after a while, so I'll continue this another time. I'll keep you posted as always!

Wilba MB-6582 (Part 4)

I finally sourced a nice Commodore 64 Power Supply for the MB-6582 from E-bay. Actually the shipping was more expensive than the Power Supply itself, but now I can finally continue. As you can see this is the newer type that came with the Commodore 64 II. I was a bit worried that this one would have different voltages or something like that, but I couldn't find an old type and I read everywhere that this type is more stable. So I decided to go for it anyway. In the worst case I could always look up an Commodore 64 II without a power supply ;)

Then I looked up the pinout of the power connector and hooked the power supply up to the mains power. I measured on the connector and it just have +5V DC and 9V AC like it should be so that was clear. Then I hooked it up to the MB-6582 base PCB and measured the power on the different test points on the PCB. Wilba advises to do this first before inserting IC's that makes sense. You don't want to blow up your precious SID chips. I measured +5V, +9V and +12V nicely where they were supposed to be so all was clear now to continue this project :)

Then I inserted all the IC's. I had some trouble doing so because I couldn't read all the text on the PCB silkscreen anymore. On the small IC's the text is actually under the IC sockets. So I looked on the MB-6582 Wiki for a silk screen picture, but couldn't find it. But luckily through Google I found a high-res picture that someone made of the PCB without components, so that helped me on. After inserting all the IC's I switched the power on again and nothing got hot and all voltages still looked great. So I guess so far so good. Next thing is to hook up the display and see if something happens. I'll keep you posted on the progress, but it is starting to become a synthesizer slowly but surely :)

Wilba MB-6582 (Part 3)

Last week the 3mm leds arrived at my local electronics shop. And since we are again covered in snow here I decided that today was a nice day to solder them in. In the picture you see the front panel with the PCB below that I made before. It is a bit of a hassle getting all the switches in the holes, but after I while of fiddling with it I got the front panel on. I did this only to fit and see if nothing was missing. Well all the leds are missing of course ;) After this I removed the front panel again and first put all the leds of the matrix in the left upper corner in and then turned it up side down.

In the picture on the right you can see the legs sticking out. This matrix is 8x8 leds to that gives a total of 128 legs only for the matrix. I soldered them one by one and cut of the legs directly so that I could better access the next one again. Now I only hope I put the leds in the right orientation. On the PCB there is a picture of a led shape with a flat end, but my leds didn't have that. But that should correspond with the short lead. At least when I have them wrong they will be all wrong. Ah that will only be a disaster in the small ;)

After this I took the front panel off again and inserted the rest of the leds and then also soldered them one by one. In the picture on the left you can see the final result with all the leds in place. Start to look nice doesn't it? Then I had a look at how the rest of the mounting has to be done in the building document. But I actually think I have a better and easier way. But I'm going to try this first before I write about it here :) I still haven't found a good C64 power supply by the way. So testing the whole thing is still not possible.

And here is a final shot of the front panel, just because it looks so nice :) From this shot you can basically see how the synthesizer works. You can see 8 voices with 3 Oscillators per voice. 3 Filters that can be put in Low Pass, Band Pass or High Pass, 2 Envelope Generators, and 6 LFO's with each 6 wave shapes. I'm not sure but I actually think those are per SID engine. And you have 4 then (4 times stereo makes 8 voices). I can't wait to light this baby up :) I presume it will be real eye candy and nice on the ears :)

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 ;)

Wilba MB-6582 (Part 1)

I bought a bunch of old 6581 sound chips a long time ago coming from the famous Commodore 64 home computer. And I was planning to build a synthesizer with them some day. And then I found the Wilba MB-6582 project on the Internet which is basically a Midibox design with 4 Pics and 8 SID chips on one big PCB. On the website is also a very nice design for a case and you can download the front panel files from there. I ordered the PCB's along with a components kit for the base PCB a long time ago and last week they finally arrived. And I couldn't wait to start on this project. Here you see some of the resistors already in place on the PCB.

The documentation for this project is neatly done online in a Wiki that is updated when necessary. It gives great information on the different build possibilities. It was originally designed for the 6582 SID chips as the name suggests. These run on 9 Volt, but it can also handle the other types of SID chips. I use the original 6581 and they need 12 Volts. The builder actually offers 4 options to build the PSU section. I chose option B because of the need for 12 Volts and I want to use an original Commodore 64 power supply to power the synthesizer later on. In the picture on the right you can see a picture where I just mounted all the IC sockets on the PCB. There are quite a lot as you can see.

Here is a picture where also the backpanel components are installed. On the left is the power switch that is actually the same switch as used in the original Commodore 64 and next to it the power connector. Then two midi connectors and next to that 4 stereo audio output jacks. Yes this baby has 4 stereo output channels :) You can also see that I installed the electronic parts behind that. This is all for the SID chips itself. It is quite dense in these parts and you actually have to install some resistors standing up because otherwise they wouldn't fit. You can also see the capacitors next to the SID IC sockets are on little parts of IC headers. This way you can swap them since for the 6581 you need different values than for the other SID types. And I don't know yet if mine actually work.

And here is a picture of the finished base PCB. Here also the PSU section is in place. I didn't put the IC's in yet. I need to run some power tests to see if I didn't make any mistakes in the PSU section. I don't want to blow up my precious SID chips :) But since they are all on IC sockets it is just a matter of putting them in. Next step is another PCB that is used for fitting the front panel components like all the leds, switches and rotary encoders. I just ordered these components from Mouser and I'm waiting for them. I also got a display from CrystalFontz in the US. If you are curious what this project is going to look like or want information to build one yourself do visit the MB-6582 Wiki at this URL: http://www.midibox.org/dokuwiki/wilba_mb_6582