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moog modular System 55 restoration
"arrived!", "2" => "different angle", "3" => "back side", "4" => "keyboard plug", "5" => "ugly cheeks", "6" => "panel removed", "7" => "modules out", "8" => "921A", "9" => "921B", "10" => "911", "11" => "911A", "12" => "903A", "13" => "rotary switch", "14" => "921B again", "15" => "THE low pass", "16" => "depanelized", "17" => "and from the back", "18" => "before/after", "19" => "914", "20" => "stripped case", "21" => "ugly varnish", "22" => "like new!", "23" => "and again", "24" => "keyboard dries", "25" => "nice cheek", "26" => "messy", "27" => "what's left", "28" => "and even less", "29" => "power supply", "30" => "fillng back in", "31" => "looks like moog", "32" => "PS completed", "33" => "almost full", "34" => "it makes sound!", "35" => "new patchcords", "36" => "before / after", "37" => "again", "38" => "and again", "39" => "finished!", "40" => "better angle" ); $dlugieopisy = array ( "01" => "This is how moog modular system 55 looked like when it first arrived. Right after unpacking and unwrapping it landed on the operation table, ready to for cliche photo of me posing like Bob Moog, but I'll spare you from seeing that", "02" => "From this angle the modular looks simply awesome, if you cover your eyes not to see terrible shape of wood case", "03" => "Unforgettable feeling when I first looked inside. It is very well thought and good designed cablng system inside, considering that nobody heard about backplanes then. And the smell of it told the truth about its age and storage conditions.", "04" => "Awfully corroded screws, and the keyboard's plug was a mess, very much like covered with zinc whiskers, but it is anodized aluminium, so I don't know what caused this", "05" => "Terrible looking keyboard's cheek, fortunately no fungus yet. Except the plywood base, the keyboard was made from solid wood, something you cannot see nowadays", "06" => "This is how it looks inside, vast space for what was inside, just a small circuit board", "07" => "All modules removed, leaving only the rails, cabling, back pannel, and lowest row of utility modules, that are mounted on hinges. Unlike the rest, the bottom row is soldered to the wiring harness, and cannot be simply unplugged", "08" => "And here starts the synth porn, showing the innards of a few modules. If you haven't recognized it yet, it's Oscillator Driver, module number 921A. It's funny to see how the components are carelesly spread all over this huge PCB", "09" => "Now this is one of very few modules with complex circuits, and double sided PCB. Thru-hole metal platted in 1974! Only serious industry used that. It's the famous 921B Oscillator. It is worth mentioning that only oscillators contained the decent quality rotary switches. After 40 years they were still working very good, and required only slight cleaning.", "10" => "Another example of too big PCB, notice the nice big empty area on the left. It's time to mention that every potentiometer used is Allen-Bradley type, hermetically sealed with very thick taper track and special (graphite?) slider block, so they should last forever. Unfortunately every one required cleaning, because the old grease and wiped particles made a lot of bad things inside. Those pots cost a fortune now.", "11" => "Dual trigger delay. Someone cleverly thought that half sized PCB would be enough. But I cannot understand why, oh why, those kind of connectors were selected for gate/trigger. The socket was probably designed shortly after the discovery of electricity. The phenolic part is held in metal ring by the force of a nail! Not to mention nasty cadmium plating...", "12" => "Noise generator, very nice front panel to work with...", "13" => "Favorite Moog's rotary switches, probably were the cheapest ones they could get at that time. Simply a nightmare. Completely covered in white-ish powder probably generated from zinc whisker growth, inside and outside. Obviously none of them rotated by reasonable force, if rotated at all. Complete disaster", "14" => "Another look inside 921B VCO, so everythng is clearly visible, very nice desin if compared to all other modules. I made hi res photos of every module like this, I hope. Also from the bottom, not to clone the PCB, but pure documentary reasons ;)", "15" => "It was emotional experence to hold this one. After all, this is THE VCF which started it all, and is now recognized by sound all over the world and cloned in nearly thousands of incarnations. The moog ladder low pass filter. In this photo you can see the capacitor banks that were switched with rotary switch (the crapy type) and the transistor ladder itself. Yellow dots show that transistors were hand matched and selected to color-coded bins. The rest of circuitry was on 2nd PCB.", "16" => "Small collection of modules, stripped down from panels and some of them have given their jacks to regeneration process. The only possiblity to see them lke this. It may hurt to see it, but anyway, it's just another electronic circuit, even if they have a soul inside...", "17" => "The same stack from the back. Although the crates seem unnecessary to be so big, it helps a lot in safely stacking and storing them in depanelized form. Notice beautiful color coded capacitors in top module. Noone makes them like that anymore", "18" => "I'm not going to ramble on what kind of process was used to achieve this, but the results are clearly aparent. Original shape of rotary switch after 40 years, and the same kind after restoration. You can see the sliding contacts behind - yeah, all of them were dismantled and thoroughly cleaned", "19" => "Sneak peek into the back of fixed fiter bank. The sqaure thingies with protruding screws are holding the (quite big) filter coils. Big panel, easy to work with, but plenty of potentiometers to clean. And this is one of only few modules that used shielded cable for audio", "20" => "All bits and pieces removed, and there was quite a lot of them indeed, bottom case ready for wood workshop. Aparently this was the side where sunlight operated over long time", "21" => "The other side of bottom case. It can be seen even at this not-so-good picture, that varnish is completely destroyed. It needed tearing down to bare wood, but there's only maybe 1mm of veneer, so very gently with heavy tools...", "22" => "After many hours of work the cases look like new.", "23" => "I'm very proud of the result, hence next picture with empty refurbished cases. The interior and bottom sides were also refurbished, no compromise here.", "24" => "Keyboard drying, AFAIR that was the last layer of varnish, so final result shown.", "25" => "Remember how this side looked like some 20 pictures back?", "26" => "What a mess inside! If there only was a source of those slider switches... System 55 uses many of those and each needs to be opened and cleaned inside, despite they are not really designed for opening", "27" => "This is what's left from the mighty moog modular. All you can see in this picture is just one entity, all soldered with wires, no connectors in between. And it had to be removed from the case in one go. On the bottom you see depanelized modules in boxes", "28" => "The \"CP\" modules being disassembled. Without the panel it's difficult to recognize what a heck is this. In bottom right corner there's keyboard frame, keyless and rubber bushings removed for replacement", "29" => "There are 4 independent power supplies in moog modular, with slight component variations to achieve required voltages. This is one of them after restoration. Very nice design, if you have a chance, go find schematics and study it. Force-sense for DC line and GND, all with single star gnd/supply point in the middle of modular case made of big screw terminal block.", "30" => "First modules find their new home in refurbished old case! On top of it - the sequencer - it is so densly wired that even without panel it still holds together", "31" => "More and more modules put together. With shiny refurbished knobs and jacks it looks so sexy!", "32" => "Entire power supply put together, only perforated cover is missing. I had to use some magic and fight for every mV in voltage budget, because the transformer was not well spec'd for 230V line. Finally the power rails were not nearly as silent as Tutenkhamon but quite close nonetheless", "33" => "Almost all in, but some of them are just empty panels, just so it looks better. Lower right corner still open to leave access to (non cased yet) power supply", "34" => "Since it's ready to play some sounds, why not establish some obvious oldschool-Berlin phattingly fat patch: SEQ controlling 3 VCOs and to the filter followed by envelopped VCA. Nice :), ", "35" => "And here are top quality hand made (not by hands of Chinese children) patchcords, using modern instrument cable and new design of slim plugs. Of course some ugly trigger cables too", "36" => "Find 147 details differring those 2 pictures", "37" => "Another example, of comparision", "38" => "Heart of System 55 - juicy oscillators, finally got their new life", "39" => "Overall look just before packing and saying good bye to the monster moog modular", "40" => "Looks much better from this angle.
And that's all folks... If you happen to have one of those in your shed or attic, I'll gladly restore it for ya to factory mint condition :)" ); if ($_GET['obrazek'] == "" || $_GET['obrazek'] == "main" || $_GET['obrazek'] < 1 || $_GET['obrazek'] > 40 ) { echo "
This is small collection of pictures made during restoration project of Moog Modular System 55 which was a pleasure to conduct in begining of year 2012. This was very difficult time because of massive amount of work in other areas and very limited time to do the moog work but after almost 2 years I recall that period as very interesting, inspiring, and worth mentioning. So I finally put those pictures here. If there's interest in moog synth porn I may put more, but I didn't want to bore you with over 300 pictures.

click the picture for higher resolution and some comments

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click here to return to picture index

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© 2013 Roman Sowa
Last revised November 24, 2013