135 posts in this topic

Hi Sauraen,
I'm compiling my parts list on mouser and just wanted to confirm:

Chip U3 - 74HC137 - 3-to-8 decoder with enable, for selecting board and sound chip

Only one chip and one bypass capacitor is needed in total for a Quad Build right i.e. Genesis Module 1?
Since I'll be using jumper wire to specify the number of the other 3 Genesis Module boards.

Thanks.

Edited by Smithy

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Yep, one decoder per 4 boards.

Yogi

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Thanks guys. More stupid questions to follow...:tongue: 

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Okay here's a legitimate question.

In the parts list is says to not populate R14.

But in the Parts Chart it says its needed for "Any board you want to include a SN76489/94/96".

Have i spotted an anomaly? 

Hmmm.png

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Just wondering if anyone else out there is building this project also?

Has anyone found a suitable enclosure for the Front Panel?

I'd like to have these things finalized before I order the front panel parts.

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@Smithy: yes, you found a mistake. R14 is DNP. I updated the page, and also fixed another minor mistake I noticed.

When you're talking about "enclosure for the Front Panel", do you mean an aluminum or plastic panel for the front panel PCB to mount under, or do you mean an enclosure for the synth?

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22 minutes ago, Sauraen said:

@Smithy: yes, you found a mistake. R14 is DNP. I updated the page, and also fixed another minor mistake I noticed.

When you're talking about "enclosure for the Front Panel", do you mean an aluminum or plastic panel for the front panel PCB to mount under, or do you mean an enclosure for the synth?

Sorry for the vagueness! I mean the enclosure for the synth!
Do you by any chance know the model of the project boxes you found? I wonder if they can still be purchased as they're perfect!

Edit: I see in your original MB FM video that its an electronics training kit. Id almost buy a kit just to use the enclosure!

 

Edited by Smithy

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For the power supply I'm thinking about going with this 5VDC 1.5A Switching Power supply.

http://cpc.farnell.com/powerpax/ptd-05015b/ac-adaptor-5v-1-5a-regulated/dp/PW02343

Would you recommend connecting 2 Voltage Regulators like the OKI-78SR-5 you suggested to it as well as the fuse holder?
I want to keep it simple, so would just like it to run from a 5V power supply only.

Also, I may be getting ahead of myself but where can I download the compiled firmware for MB Quad Genesis?

I checked the MIOS SVN, especially trunk/apps/sytnhesizers, expecting it to be there.

 

 

 

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The cases are from Cadet electronics trainers from the late '80s which I dumpster-dived a few years ago. (The more modern ones have plastic cases and are somewhat smaller.) I actually have one case left, but it might not be worth it to ship, as it's heavy steel. I might recommend you just build something out of wood or whatever.

Any clean 5V power supply should be fine, just be aware that the front panel can theoretically draw up to 1.2 amps (if it turns on all the LEDs at the same time and then crashes so the matrix isn't being updated). Under normal use it's much less than that, probably about 300 mA. The supply you mentioned should probably be fine.

The source code is at http://svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fsynthesizers%2Fmidibox_quad_genesis%2F ; it hasn't been updated in a while, but when I get home (I'm away right now) I'll put up the latest version. I never put up the hex file, I was expecting everyone to compile it from source, but I guess that's dumb and I should put up the hex file too. There's more features done, including an automatic velocity sensitivity thing--but still saving isn't finished, oh well. :)

Edited by Sauraen

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Thanks a lot man!
Technobreath has volunteered to design a wooden case.
I wonder if its possible to get the dimensions of your own case when you get the time? Maybe the angle of the slope of the wedge shape also.
And if its possible to make them even smaller if theres a lot of space.

Looks like the missing parts of the puzzle are coming together with help of the community! :)
 

Edited by Smithy

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The aluminum front panel is 15" x 11" (38.1 x 28 cm). The dimensions of the rectangle around the border where the screw holes are is about 36.8 x x 26.4 cm. The case is 10.5" (26.7 cm) from back to front, 10.8 cm tall in the back, and 3.8 cm tall in the front. Everything fits reasonably well inside--there's some extra space, but especially in the front a lot of that is taken up by the front panel. The height in the back is just right for the stack of Genesis boards.

large.finished_inside.jpg.a282bdd85dac4d

large.finished_inside2.jpg.459682a854f13

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Hi.

I appreciate the metric. Thanks. I'll get right to it :).

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Thanks a lot Sauraen!

I didn't realise that you stacked the genesis modules on top of each other, I like the idea of using headers instead of cabling for the data lines and power lines.

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@Sauraen - can you provide dimensions of the PCBs in the back mounted vertical? + how deep the CS PCB is from the back of the CS alu plate - basically the height of the standoffs + PCB - is it standard 1.6mm PCB? I'm fishing for if the PCB sandwitch (within the given dimensions) can be mounted horizontally.

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Just now, technobreath said:

@Sauraen - can you provide dimensions of the PCBs in the back mounted vertical? + how deep the CS PCB is from the back of the CS alu plate - basically the height of the standoffs + PCB - is it standard 1.6mm PCB? I'm fishing for if the PCB sandwitch (within the given dimensions) can be mounted horizontally.

This is answered in the wiki me thinks:

http://wiki.midibox.org/doku.php?id=mbqg_fp

 

"The spacing between the underside of the front panel and the upper side of the PCB is about 0.27” (7 mm), which is originally defined by the encoders and the 3D printed buttons are made to match this. I used 1/4“ nylon spacers/standoffs from eBay plus a flat washer (4-40 or M3) to achieve this spacing. I used 0.75” 4-40 screws to put together the front panel, in which case the depth of the assembly was 0.75“ with the electrolytic capacitors and pin header / IDC connector sticking out past this. The panel and PCB can be fastened together with 4-40 or M3 screws. "

Edited by Smithy

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Technobreath too lazy to read all details in the wiki :P lol. Good, good.

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23 minutes ago, Smithy said:

Thanks a lot Sauraen!

I didn't realise that you stacked the genesis modules on top of each other, I like the idea of using headers instead of cabling for the data lines and power lines.

Actually it might be worth adding this information to the Wiki. I can do it if you like, and maybe embed the photo you sent.
What length are the nylon spacers you used to stack the Genesis Modules?

And also the male headers and female sockets for the headers?

I see the 4th Module is using longer spacers but I presume you were just using up what you had to hand.

Edited by Smithy

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Trying to hit all the questions above:

  • I use metric all the time except when the parts I'm using are themselves measured in English system (e.g. 1/4" spacer or 0.1" DIP spacing). I try to convert for people. (proceeds to not convert below...)
  • The Genesis module sandwich should be mountable from the bottom rather than from the back, its width is about the same as its height.
  • The Genesis modules were designed to be stacked like that--you will need a lot of cables otherwise, and some parts like the mixing circuit will be more of a pain.
  • The reason the spaces are inconsistent is as follows. The wider spacer is a 0.75" threaded aluminum spacer. The top three boards screw into it from one side, and the bottom board and the case screws in from the other side. I didn't have screws long enough to go through all four. The other spaces are 2x 1/4" for a total of 1/2". As long as you have about that much clearance between all the boards, the spacing doesn't matter.
  • The headers are long pin sockets for Arduino shields, added the info to the wiki. The particular part looks like it's obsolete on Mouser, but once you see it you should be able to get something similar. They'll be longer than you need, clip the ends of the pins to fit.
Edited by Sauraen

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Here's a draft of the idea me and Smithy has been discussing. An all wooden case. Since it is wood, the idea was to put an alu plate inside where you want to mount the PCBs (wood is more or less alive - I was thinking either MDF or plywood). Those are illustrated with blue panels in there. With this design you can hide all mounting screws (except the ones on the CS panel itself - I can't do anything about that - and I just praise the powers that Sauraen didn't do a JB-Weld like experiment with that - because frankly that sucks, and is not robust enough). The only thing I can think of that would make a surface virtually free of screws (like professional system designs mostly look like) would be if you TIG weld alu standoffs to the panel itself in the correct place - and to be totally clear - TIG welding is not for everyone to do correctly, and also it is not for everyone to own or have access to these tools :) - so better stick to the through hole screws.

If this is something the people think is interesting, I can do a model in exploded view with all parts and dimensions and building tips. Even tho I have had a job in the tech business the last 10 years old - a carpenter is what I'm am in my heart :).

If you guys want this, I can spend some time doing this for you, so there is an alternative to the sorta special case Sauraen uses.

By the way, I have a buddy that owns a large sheetmetal shop, and I talked to him about replicating these cases with sheetmetal. He said, for large quantities, no problem to do it cheap, but for such low quantities, it is not worth the effort. You gotta pay a guy there to make a CAD drawing of it, and then some hours of work in the metal shop. So at least here in Norway, it will not make any sense to offer a custom case made from metal. It is just too expensive. Now, if someone absolutely want that, and are willing to pay, we will fix this too, but it will be a rather foolish thing to waste money on :). Besides - wood is modern nowdays :P.

What do you guys think about this? Something I should invest some hours in? If there is absolutely no interest for it, I see no point in doing it, so give me a hint if you would be interested in building one please :).

Genesis Case Wood.png

And please, I am open for suggestions to the design of it. It is a bit hard to design a case for something I don't have in my hands, so input is most welcome :).

Edited by technobreath

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It looks cool, and thanks for spending so much time on a project that isn't even yours! I like the idea of having the PCBs and back panel stuff mounted to sheet aluminum.

But I think the most important thing is that whatever case "gets designed", if that's even necessary for the community, is something that future people can build themselves with minimal effort. I don't think trying to hide screws is very important. I think what's most important right now is that Smithy and the handful of other people who have purchased front panel boards from me can get their hands on a case relatively quickly and cheaply. When creating this project, I wasn't really expecting other people to build it just like mine--I wanted to give them the resources that I had developed, but let them do stuff like the case and I/O themselves based on general MIDIbox knowledge. For instance, I would give you the dimensions and layout of the back panel, but there's no reason other people need to make it the same way I did.

Just one nitpick about your design, there is already a "MIDIbox Quad Genesis" logo, you can extract the vector art for it from the front panel layout file. Open the file in Front Panel Express and save as SVG, and then open it in Inkscape or your preferred vector editing software and get rid of everything but that text.

 

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@Sauraen

Hi. This was really a thing born out of a question from Smithy if I could help him out and show him howto build a wooden case, and if he is the only one wanting one, I figured it wouldn't make much sense spending much time on it.

I also doubt that "designing" a case is necessary for this community :) - It is just a fancy word. Woodwork is second nature to me, so I call it building a box :D. The case isn't really a design. It is a drawing to show how a wooden version of your case can be put together. :).

But, there are many people who find what I call basic and simple woodworking a challenge, and might not know how and where to start, what materials to use, and if they build a wooden box making sure they secure the PCBs on a dead surface like aluminium etc. Because of this, it is extremely important that if I make some build plans for this, that it is as simple and straight forward as it can possibly be. I appreciate you pointing your fingers to this issue, but don't worry, Building this box is as straight forward as it gets.

As for the hiding screws :) Some thinks it's important, some don't. This box you can do both. It's really just a matter if you install the sidepanels or not :).

Smithy set the standard for me to follow on this one - The terms were that it should be possible to build with simple hand tools, like a battery drill and a regular handsaw plus something to cut the alu plates if you need to (also handsaw with proper blade) - you know all about this of course ;).. I take it for granted that people know how to use sandpaper to finish up the thing a bit afterwards and also know how to operate a spraycan of paint if u want to paint it hehe - if not - youtube. If still not able to do it - u have no business doing it hehehe.

You're right, there's no reason why people should limit their cases to exactly how you did it. But it is a good and practical case you got there, so it is not a bad idea to have woodplans for similar case on the forum. But people do whatever they like. Since I promised to help Smithy out with this, I figured that I might as well let others also have the plans I make for it. When I design cases, it is far more complex designs than this (but that's just me taking at least as much pride in the designing of the system as actually owning and using it hehe). I usually go for wooden models which can then become finished products made from plastic or fiberglass with the help of epoxy casts and clay etc.

As for the logo I slapped on there :D - Have you seen Jugde Dredd? "I knew you'd say that!" - Hehehehe. I meant nothing else by it than to show what the case was all about. I didn't expect anyone to think twice about it. It was just something I slapped on there last minute in photoshop because I thought the showpiece lacked graphical hmmm details hehe (while I thought - yeah that looks cool) :D. It was most certainly not my intention to step on your toes in any way - you were very polite about it hehe. But of course I expect the proper logo to be used, it's not like I am the creator of it.

The thing about spending time on a project that is not mine. First - I don't spend as much time on this as you might think hehe. The second thing is that I've been around midiboxland in one form or another since forever way back, and I don't know how it works these days, but back then one of the major strenghts of this community was contributing where u can, willingness to help others out with whatever you could help out with etc. So that's why when my good buddy Smithy ask me for help, I say of course!! :).

I asked you for the dimensions of things and your thoughts on your own case design and system design really because I need to make sure that when I contribute with something as "important" (understand that correctly) thing as a case - it need to fit the things that are going inside it hehe :) - it would be very bad to make someone build a case from my plans just to find out it doesn't work at all.

Anyway - this post has become FAAAR longer than I planned for. Just wanted to clarify my role in this, and clarify what this fancy case design shit was all about :).

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I have to say I quite like the alternative Genesis Digital FM Synthesizer logo.

its a bit like having a Commodore logo on the mb-6582.

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Right now I'm trying to figure out which LED colour scheme for the full LED Rings.

Theres 4 options here, basically the encoders are turned all the way clockwise so all leds are illuminated.

21014784_1277968158997465_544862855_o.pn

 

The first option shown (ATK Rate) is how Sauraen has his configured, (except with Blue LEDS instead of green.)
Technobreath prefers this option.
I think the first and second from the left look good.

The 3rd option has a yellow LED to indicate the midway point. 
And the 4th is like how a dj mixer or mixing desk shows the volume on a channel, although looks a bit weird in a circle.

Thoughts?

 

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I would either go with the first, as that's what I did, or make them all the same color. The software will illuminate the 0 LED (lowest one) whenever the encoder is "active", i.e. there's a value being shown on it. Or, of course, show a value with other LEDs lit. But the point is, if there's no value being shown, all the LEDs will be off, so you can distinguish "zero" from "none". That's why I made that LED a different color, but there's not much need for it. I don't like the other schemes, they imply there's a difference between the other LEDs, when there isn't.

Also @Smithy the most recent build of the code and the project file are up. One feature that I've been meaning to add, and maybe I can sooner or later, is a self-test mode for the Genesis boards where it automatically figures out which ones you have installed and what their clock speeds are. This will be helpful for you debugging the hardware, since the software you get with this project is a lot higher level than that.

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