MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

Arturia Microbrute Keyboard Chop (midi module conversion)
MUFF WIGGLER Forum Index -> Music Tech DIY  
Author Arturia Microbrute Keyboard Chop (midi module conversion)
Rex Coil 7
Love the tone. Love love love the tone! Keyboard blows ... it had to go.



Keybed is attached to main pcb via a very small and very delicate ribbon connector. Carefully remove the connector from it's socket. There now, there's nothing else between the keybed and the rest of the synth.

(NOTE: I did this step and stopped here ... I then tested the synth's functions with the keybed disconnected. I used an Alesis Micron as a keyboard controller, connected it's midi out to the MicroBrute's midi-in ... you know the rest ...).






A few screws and the keybed chunks come right out. It's interesting to see how manufacturers buy these little keybeds. You can see they come in octave chunks, and with a single "C" key to fill in the end gap and create an even number of C-C octaves. There are no return springs beneath the keys, they simply use a "living hinge" (oh how I dislike those things, they NEVER live very long). The bottom of each key has a raised area that makes contact with the tactile switches that are the actual key switches beneath the keybed. Pressing a key depresses the tactile button and we get a note-on signal. The key's travel is limited at the bottom by the Microbrute's plastic frame, and the key's upstop felt is attached to the metal frame that the diode grid is mounted to. That's pretty much the total heapin' helpin' of info on the mechanics of the cheapo mini keys.











Here's the keybed's pcb ... I "candled" it (backlit so that I can see any pcb traces that may be hidden within the layers of the pcb) ..... just pretty much your standard diode grid type key/note triggering setup. Nothing new here, but well done nonetheless. Not only that ... rippin' cool image, que no? I think that may become my avatar ....


nanners







(CONTINUED NEXT POST .... )



Mr. Green
Rex Coil 7
PAGE TWO ....

Here's the first bit of stuffs that got removed .......





Bagged, masked off as well as could be done ..... preparing for surgery ....







The first cut .... it's always the most difficult to do. Once it's done the rest is easier .... not ~easy~ by any means .... but easier. For me, these type of mods are always kindof nerve wracking, on edge throughout the process.







So, it's not really rocket science here ..... do some thinking about how and where the cut needs to be. This is based on how one intends to cover up the gaping hole that will be left over when the chop is done. In my case I used a section of prefab extruded aluminium angle that happened to fit pretty well up against the open edge. That said, I planned the cut accordingly. It should be noted that multi-faceted objects (like the Microbrute) can be difficult to merge your cut into the lines/shape of the device. That said, after seeing how the cuts came out, I'll approach it differently on my next one (wink). While this "got it done" I've a better plan for a more refined looking job. The first one of anything that I do tends to be less than beautiful. People like me rely on the slack that one is given with the word "prototype" .... haahaa!







So here's the roughed out job in it's "so far" condition. The bottom plate has been cut, however I've yet to rivet an end piece to it as well as finish up some details. I'll post those pics as this moves forward. So far I really like how it's working out. While I'm mounting it within my modular system, there's a number of other ways to use this. It's dimensions are very close to Euro modules in this configuration, one cannot help but imagine it as a Euro mini synth module (a factory built unit, not my little hack-n-chop stuff).






Thanks folks ... more to come, it's a time thing.

hihi
Rex Coil 7
And by the way, this voids the warranty. Some things simply beg to be done, damn the torpedos - full speed ahead.

thumbs up
mckenic
love

I ADORE this!!! Thank you for posting!!! As someone with very little space on my desk and someone who cant play keys apart from chicken-picking them, this is wonderful!!!

thumbs up

[EDIT] Just looking at my Micro here... the bottom end, after you made the cut... the part that acts as the key stop (is that the right term?)... would that fit in the bottom? With just a little strip of plastic to cover the hole left by the key height?

Like moving the bottom up in this pic - if that makes any sense...
GGW
I've got the MiniBrute and like it a lot. I'd hoped that Arturia would have released a version of what you're doing rather than that tiny keyboard. I'd certainly go for that.

Is that casing you are cutting metal or plastic? How did you make that cut? I'm trying to visualize a design where the key part and sides get cut off and the synth gets put in a wood box case. The necessary parts to save would be the top and back, right?
Rex Coil 7
Member McKenic ..... ~no~ I do not believe that the keystop will work as a filler for the hole left over from the keybed removal. The pics show here that the gap is roughly 32mm tall and the plastic keystop piece is only roughly 18mm tall (see pic).....



The 1.5" x 1.5" x 1/8" aluminium angle extrusion that I used for the filler (and base support) seems to fit ok enough to be eligible for use. In the picture below you can see the MicroBrute's frame and the opening I created when I cut it, as well as the aluminium angle that I used to cap the gap. The pic shows what kind of gaps you're dealing with, as well as some loose dimensions.





In the pic below the overall width that needs to be covered up is 324mm .... I squared up the other end of the ruler dead on ......









Here's what it looks like after chopping and clean up ..... it sure would be a great factory offering! Oh well ..... it is what it is .... if we want them as desktop shorties we have to make them. After cutting you can see that the two sides, back, and control panel (top) are all still intact. Those parts stay with the pcb and pots/switches ... the bottom plate (steel) is all that comes off when the bottom screws are removed. You're left with the entire contents of the synth still mounted into the plastic case, and a steel panel that is the bottom cover.

So when the keybed is cut off, the two sides, rear panel, top panel are all left totally intact with all of the controls and I/O jacks still mounted firmly in place. This is one of the easiest chops I've ever done, essentially upbolt the bottom plate, disconnect the keybed, removed the keybed, and cut the case. No wiring, no soldering.





And .... the finished work. Well, nearly finished ..... that gaping maw still must be capped off and I still need to cut the bottom plate (thin guage steel). I'll use a 4" angle grinder with a cutoff wheel to trim the lower metal cover to size. File to dimension and smooth out the edge ... remount .. done! Pop rivet the 1.5" angle aluminium angle to the bottom cover plate, install the works and make sound.





thumbs up
mckenic
applause Thanks Rex! That makes a lot of sense - I was thinking of it just like chopping out the keys and sliding everything up to (almost) match.

If I can land a white one to keep stock Imna butcher *ahem* I mean mod mine too!

It looks so CUTE!!!

thumbs up
Rex Coil 7
GGW wrote:
I've got the MiniBrute and like it a lot. I'd hoped that Arturia would have released a version of what you're doing rather than that tiny keyboard. I'd certainly go for that.

Is that casing you are cutting metal or plastic? How did you make that cut? I'm trying to visualize a design where the key part and sides get cut off and the synth gets put in a wood box case. The necessary parts to save would be the top and back, right?
Top, back, both sides, and rear I/O panel are all one single piece of plastic that the innards all reside within. A sortof upside down three sided bathtub. There's a number of plastic standoffs that the pcbs are mounted to, as well as eight plastic standoffs that tie the control panel to the bottom panel via mounting screws (eight remaining screws, originally there are twelve ... the four mountings and their screws along the ends of the keys are removed in the modification).

no floppy bottoms here....

And while I'm thinking of it .... there are so many standoffs and mounting points on the Microbrute that removing the keybed and cutting the case does not create a floppy/bendy unsupported bottom panel. There are still eight bottom panel screws left in the assembly after cutting it down. Four of which are evenly distributed across the middle of the MB. That said, where I cut it is within about 15mm from a row of four standoff screws.

If the cut down Microbrute is turned on it's back and the bottom panel is pushed down on, it will not sag or bend or collapse due to losing any of it's mounting points from cutting it down. The bottom panel is not left unsupported along the trimmed edge, the four bottom panel mount points that originally supported the middle of the Microbrute are now very well positioned to support the (now new) southern edge of the of the cut down MB.

So there's that ....

smile
Rex Coil 7
GGW wrote:
I've got the MiniBrute and like it a lot. I'd hoped that Arturia would have released a version of what you're doing rather than that tiny keyboard. I'd certainly go for that.....


Agreed! Actually I'd like to see a glass keyboard, er .. I mean a touch screen kybd .... but one that's not just some touch screen kybd .... do it like Animoog .... make it a control surface.

Yea .... yea ... I know ..... money money money, right? Keep costs down so that it remains an entry level synth (otherwise why make it out of plastic?).

It's all just dreamin' anyway ..... all's fair in dreamland, no need to get all "real" about it by injecting sensible notions such as cost control when we're dreamin about little fantasy synths. smile

But still ... yea ... Korg type glass "keyboard" but make it work/look like Animoog, and maybe even throw in assignable functionality of the x-y controller ability of each "key" via desktop pc editor. There's an app called "TF7" that is yet another Yamaha DX7 type operator based IOS soft synth. It uses a grid type note entry, and each "cell" of the grid allows pitch bend of up to one octave in either/both directions in realtime. That type of ability on each "key" of the Animoog type touch screen kybd for a Microbrute type synth would be the dog's balls.

Sortof a Volca style controller (a thin strip across the width of the instrument), with Animoog look and ability, with the added pitch bend/whammy side to side ability that TF7 provides per note. Add controller sequencing to the little sequencer (y'know, where you can write a musical sequence, then during playback you can add controller inputs that will be recorded along with and added to the saved sequence).

Beats polyphonic aftertouch by leaps and bounds!!!

Yea, I know .... that just added $50 bucks to the retail. Perhaps more. Again ... dreamin' here! All's fair! smile
Starspawn
Good job! Is it possible to remove spring in pitch bender to get a coarse pitch bender?
Risto Esquina
Nice, tidy work. Hack jobs always make me cringe, but this clearly isn't one. You should send this to Arturia and tell them they can have the idea if they cut you in for a commission on each unit sold.

Eyeballing it based on the MU modules I'm guessing this would fit into a very compact 13" x 6" box; smaller still if they dropped the now redundant pitch and mod wheels (which, frankly, are a bit rubbish on the Arturia gear anyway).
bitflip
Whoa!! Very nice! applause

My micro is visibly shaken by this work, and MS-20 mini is sweating... hihi

Do you have any plans for the leftovers? I've been thinking of doing something like this, but would hate to throw out stuff that I haven't figured out a use for. Does anyone have any ideas for re-purposing keybeds and such?
Rex Coil 7
bitflip wrote:
Whoa!! Very nice! applause

My micro is visibly shaken by this work, and MS-20 mini is sweating... hihi

Do you have any plans for the leftovers? I've been thinking of doing something like this, but would hate to throw out stuff that I haven't figured out a use for. Does anyone have any ideas for re-purposing keybeds and such?
Oh yea .... those leftovers have some stuffage in them that can prove handy if the proper mood strikes me. Thirteen note-on buttons with the diode grid to match, all ready to go in that pile of stuffage.

In the end it's still a "midi keyboard" when it's all said and done (the leftovers, I mean). At least it can be with the addition of the right things. There are DIY kits available that convert standard analog switch information into midi notes, such as the kit I used to convert old Hammond bass pedals into midi bass pedals ... about $60 bucks worth of conversion tinkertoys makes it all happen. "Midi encoders" and "Midi decoders" are what you'd want to search for via Bing/Google.

As for the workmanship ..... BLECH! It's some of my most hack-job work. I had a helper (my handicapped live-in brother) who actually did all of the cutting and file work on the aluminium angle. Before his disability (around 1990) he actually worked in the rocket motor shop at Lockheed Martin in Sunnyvale California. So he's as much a metalworker as I am, however his skills aren't as honed as they once were. I'm still recovering from some open abdominal surgery so I am as yet unable to do heavy handiwork (like using a hacksaw or a manual press ... anything that exerts is out for another few weeks). So ... "Thanks Jeff!" ....

thumbs up

I'm hoping to be back at my rightful place at helm of my own machine shop and electronics bench as soon as I heal up a bit more. I waited nearly 1.5 years for my turn at the VA to get the needed surgery, I'm not about to jeapadize the results by overdoing things. I have to reign in my ambition andwork ethic otherwise I'll be back at square one with the VA ... and yet another lost year + fekking with that circus act.

Ugh .. sorry ... spilt my personal problems all over this thread.

Onward! smile
Rex Coil 7
Starspawn wrote:
Good job! Is it possible to remove spring in pitch bender to get a coarse pitch bender?
Yes! They may be disabled, then you can set the pitch wheel range to one octave ... and when you do that the "glide" (portamento) control then has full control over how responsive the pitch wheel is! I shit you not, Brah. Set the pitch wheel range at 12 semis ... now use it at full sweep and when doing so adjust the slew knob and you'll hear the pitch wheel's response get more and more sluggish. Reduce the glide time and the pitch wheel becomes "realtime" rather than slowed and slewed.

I gotta jet for the time being, when I return I'll post pics of the pitch wheel assy, GOOD ones, shot with the macro lens. Btw ... that macro function ... it makes every cut look as though I used a friggin chainsaw to do the cuts on the MB's housing. I used a 24tpi hacksaw (24 teeth per inch). The blade is a 30+ year old swiss blade I've been nursing along since 1985. I'm quite attached to my favorite metalworking tools.

smile
Rex Coil 7
Risto Esquina wrote:
Nice, tidy work. Hack jobs always make me cringe, but this clearly isn't one. You should send this to Arturia and tell them they can have the idea if they cut you in for a commission on each unit sold.

Eyeballing it based on the MU modules I'm guessing this would fit into a very compact 13" x 6" box; smaller still if they dropped the now redundant pitch and mod wheels (which, frankly, are a bit rubbish on the Arturia gear anyway).
The wheels are still very much part of the game, at least in my system they are. I plan on mounting an iPhone on the left side of the wooden synth cab, so when hands are placed along that edge of the cab to use the pitch wheel the fingers that wrap around the edge of the wooden cab (while using the wheels) are now making contact with a touch screen iphone that is mounted on the side of the cab next to the MB wheels. TouchOSC or MidiTouch (et al) offer the means to make the touch screen phone into a proper CC controller. I mean, y'know, my fingers sortof naturally "wrap" around the side edge of the wooden cab when I use the wheels, so why not mount another touch controller where my fingers reside when I use the wheels?

wink

Even if one were to just mount the MB as a desktop unit the iphone-on-the-left-side trick will still work. Hell for that matter I guess that idea would work on any performance keyboard, just velcro a touch phone to the side endbell and git bizzy!
Rex Coil 7
Thank you for the encouraging replies, everyone. There's still more to add to this thread, I've yet to post the bottom panel cuts, as well as how I did the rest of the chop.

Stay tuned, same bat time, same bat channel.

cool
mckenic
applause

Thank YOU! Very inspiring and fun work - but do FFS take care of yourself thumbs up
Rex Coil 7
So here's one of the variations I ended up doing. It's formatted as a tabletop or stompbox setup. A bypass footswitch would easily fit on the lower right corner within the fenced off area (where I put those drawer pulls to protect the MicroBrute's controls from errant footstompery).

I guess the takeaway here is that the Arturia MicroBrute can be fairly easily modified in this way to produce any number of mechanical configuration variations. It sounds good enough to warrant these efforts, that's my feelings on it at least.







Those enclosures aren't just sitting there, they're all screwed down solid. The lines drawn on their tops were for cross drilling each enclosure to run wire looms between all of the enclosures. Use your imagination regarding their use. In the end I stopped right here with this project, but not because I abandoned the isea and gave up on it. Hardly.

I became so inspired by the sounds I was able to produce using my brother's two-MicroBrute setup that I moved on .... here's a peek (I'm posting a project thread for the unit pictured below .... I'll add a link to this thread when I post the new project ... say .... two hours or so?)



Now that I think of it ... this single chopped MicroBrute project may not actually be ~dead~ ..... this thread may show up again in the not to distant future. I have an idea ....... wink

nanners
soh
Inspired by Rex's work here, my friend did a chop on my Microbrute... feedback welcome smile

I don't have permission on this board yet to upload a photo but you can see my tweet here: https://twitter.com/sohear/status/1028771138162360320
Rex Coil 7
soh wrote:
Inspired by Rex's work here, my friend did a chop on my Microbrute... feedback welcome smile

I don't have permission on this board yet to upload a photo but you can see my tweet here: https://twitter.com/sohear/status/1028771138162360320
Never in a century would I have thought one of my ideas would enable someone that needed enabling.

I think you've got it turned around there ... it's you that has provided the inspiration, Steve. Not me.

I'm glad to learn someone is given the opportunity to put more music in their lives by one of my little notions.

Best wishes. Brian.
KJX
does the octave switch work with the keyboard disconnected?

or how does that work if you want to put the Microbute in the same octave as another synth you are connecting via CV or MIDI?
MUFF WIGGLER Forum Index -> Music Tech DIY  
Page 1 of 1
Powered by phpBB © phpBB Group