I'd like to make cheap midi controlled LED's

From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive!

Moderators: Joe., luketeaford, lisa, Kent

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

I'd like to make cheap midi controlled LED's

Post by Johnisfaster » Sat Mar 20, 2010 3:53 pm

I've got a couple of machines in my studio that I'd love to have a little LED on that displays when events are happening. It occurs to me that a simple MIDI device that lights up LEDs and a simple max patch should do the trick. But I'd like it to be cheap. Like under $100 would be awesome.

The plan is to add some led feedback to my bcr2000 for when I use it as a step sequence. I can send midi to the buttons which gives visual feedback but then I can't use the buttons for anything other than visual feedback=lame.

Now that I think about it there might be a dozen USB ways to do this. I'd love ideas. Thanks.
JensenJohn.bandcamp.com

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Sat Mar 20, 2010 3:54 pm

Damnit I'm in the wrong forum. Somebody please move it? sorry.
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Sat Mar 20, 2010 4:31 pm

arduino's gotta be the cheapest. A Teensy++ board can be embedded anywhere.
total cost would be around, what... 30usd on the cheap?

I mention the teensy++ because it's 24usd and has 46! output pins. That's gonna end up being less than a dollar per computer-controlled light. Plus, you can add jacks to it relatively easily and use the whole thing to trigger your modular and such too.

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Sat Mar 20, 2010 4:34 pm

oh holy shit that sounds perfect for both the lights and triggers

thanks!
JensenJohn.bandcamp.com

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Sat Mar 20, 2010 4:37 pm

so you've got to program the device itself? How difficult is that?
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Sat Mar 20, 2010 7:06 pm

it's arduino-style. Basically what you want to do is pretty much what the tutorial code does. It takes some work, but that's code for ya. There used to be very few freebies in this scene - but now there's this:

http://www.maxuino.org/
-which really simplifies connection to max.

a

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Sat Mar 20, 2010 7:50 pm

Sweet, that looks somewhat doable even for a dunce like me.
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Sat Mar 20, 2010 7:52 pm

it does take work, but the rewarding feeling of it all is so cool.

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Sat Mar 20, 2010 8:17 pm

See the soldering of soldering of some LED's or even some knobs n' buttons doesn't bother me, thats easy. But some reason coding the device itself is really intimidating to me even though it looks relatively easy I don't fully understand it. Seems like theres gotta be a USB device that is pre programmed to send votage to a set of soldering points.
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Sun Mar 21, 2010 6:06 am

Johnisfaster wrote:Seems like theres gotta be a USB device that is pre programmed to send votage to a set of soldering points.
sure - Livid Builder is one:
http://www.lividinstruments.com/hardware_builder.php
Image
"But Andreas, what's the catch?" - I'm glad you ask: It's 189 dollars just for the brain. Yup. Compare that to 20-25 dollars and you get why I recommend the Arduino.

There aren't any devices that have "soldering points" - what you do is connect a prototyping board to the headers and solder from there.

User avatar
Tim Stinchcombe
Uncommon Wiggler
Posts: 1420
Joined: Fri Mar 13, 2009 1:55 pm
Location: Cheltenham, Glos, UK

Post by Tim Stinchcombe » Sun Mar 21, 2010 12:11 pm

Are you after something that simply checks for MIDI activity? Googling quickly found this, really simple:

http://www.elby-designs.com/midi-interf ... matics.pdf
Top page: http://www.elby-designs.com/midi-interfaces/others.htm

Or do you need an indication of a specific MIDI code, or perhaps just activity for a specific 'channel'? One of Penfold's little books has a small (read 5 ICs) circuit, a 'MIDI comparator', which will blink an LED when it sees a specific message, set by toggle switches. It is in 'Practcal Electronic Music Projects', RA Penfold, Bernard Babani Pub., ISBN 0859343634 - a bit of concerted Googling might reveal a copy of the schemo online somewhere...

Tim

User avatar
JP
Ultra Wiggler
Posts: 928
Joined: Thu Jan 07, 2010 5:07 pm
Location: NJ

Post by JP » Sun Mar 21, 2010 12:18 pm

That was going to be my question. Are these machines already midi accepting? Or are you looking to midi retrofit them and add led during that process.

If it's just that you have machines with Midi that you want to blink when they are doing stuff, it might just be as simple as finding points in the circuit where power flows when they are doing something and wiring an LED in parallel to it. You'd need a meter and a lot of time, and take care not to short anything, but I'd think that should work.

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Sun Mar 21, 2010 4:09 pm

Well the first projet would be the bcr2000 which does accept midi. I want some simple LED's in a row of 8 above the buttons. That way I can devide the unit into 8 "drum programmers" with visual feedback of which drum is being triggered when. Really the LED's would be little more than a peak indicator although I don't need them to show a range of volume or anything just "bang bang bang this sound is being triggered! flash flash" simple feedback like that can really help you know whats going on when you've been fiddling knobs for an hour.
JensenJohn.bandcamp.com

User avatar
Tim Stinchcombe
Uncommon Wiggler
Posts: 1420
Joined: Fri Mar 13, 2009 1:55 pm
Location: Cheltenham, Glos, UK

Post by Tim Stinchcombe » Sun Mar 21, 2010 5:29 pm

Johnisfaster wrote:Well the first projet would be the bcr2000 which does accept midi. I want some simple LED's in a row of 8 above the buttons.
I'm still not sure if I've got this right - this thing:
http://www.behringer.com/EN/Products/BCR2000.aspx
('set the controls for the heart of the sun' comes to mind...) can be programmed to output different MIDI signals (notes?) on a number of different knobs, and then runs some kind of 'sequence', and yet when it is running, gives no visual indication of which knob is currently active? Or is that backwards, and the unit is merely accepting the MIDI info on different knobs and doing something nifty with it? Definitely not up to speed yet... :despair:

(Although to be fair, I think I understand what you are asking for, I'm just a bit surprised that this thing doesn't already deliver it!?)

Tim

User avatar
JP
Ultra Wiggler
Posts: 928
Joined: Thu Jan 07, 2010 5:07 pm
Location: NJ

Post by JP » Sun Mar 21, 2010 10:07 pm

Johnisfaster wrote:Well the first projet would be the bcr2000 which does accept midi. I want some simple LED's in a row of 8 above the buttons. That way I can devide the unit into 8 "drum programmers" with visual feedback of which drum is being triggered when. Really the LED's would be little more than a peak indicator although I don't need them to show a range of volume or anything just "bang bang bang this sound is being triggered! flash flash" simple feedback like that can really help you know whats going on when you've been fiddling knobs for an hour.
Are you using all the inputs on teh BCR, you can target the encoders at the top or the two rows of buttons under them, all 3 of those rows of 8 have LED feedback, which you can tweak to do things you want. I'm not sure but I don't think they can be indepedant of there input device so you'd need one of those rows spare.

If you want to go DIY, arduino might be your solution, it would be easy to squeeze into the BCR case, and you could just add another usb port (which would mean you'd need two cables). With the arduino you could just write a ax patch (or get someone to write you a max patch) that just listened to a series of midi notes and triggered the arduino to light the LED's. It's relatively basic stuff. and would be cheap.

User avatar
urbanscallywag
Ultra Wiggler
Posts: 937
Joined: Sat Sep 05, 2009 10:20 pm
Location: San Diego, CA

Post by urbanscallywag » Tue Mar 23, 2010 12:12 am

i would use an AVR or other microcontroller as suggested, and tap off the MIDI post opto-isolator. no other connection is needed, you can just send the drum data on the same MIDI cable as the BCR.

detecting MIDI note on then turning on/off an LED isn't a difficult task. 8_)

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Tue Mar 23, 2010 9:10 am

yeah I think the bcr IS controllable over midi, the lights on the buttons as well... so what you need is *more* lights, John?

Get in touch with Bjorn, he's done a ton of MfL work with the BCR by now.

@urbanscallywag It's not just a midi activity monitor John is looking for, I don't think. It's specific lights that can be lit up by software... and the bcr receives midi over USB as well, which is why I'd definitely use an arduino inside the device.

User avatar
urbanscallywag
Ultra Wiggler
Posts: 937
Joined: Sat Sep 05, 2009 10:20 pm
Location: San Diego, CA

Post by urbanscallywag » Tue Mar 23, 2010 10:35 am

ah, i figured he wanted certain LEDs to be turned on based on certain drum MIDI messages.

i'm not sure how you would be able to tap off the already installed USB without putting a small hub inside or something. i also never understood arduino instead of just AVR (probably cause i can never remember how to spell it. :oops:). i still think sending the data over MIDI is a good idea.

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Tue Mar 23, 2010 10:56 am

that's my point; put the arduino inside the case but have its own separate USB connector. Easiest way to do it.

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Tue Mar 23, 2010 3:14 pm

wetterberg wrote:yeah I think the bcr IS controllable over midi, the lights on the buttons as well... so what you need is *more* lights, John?
I know that sounds crazy, but if I were to use some of the buttons for visual feedback (say scrolling lights or activity monitors) then they are no longer useful as buttons as buttons need visual feedback as well. Thats why I'm looking for alternatives.
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Tue Mar 23, 2010 4:24 pm

Johnisfaster wrote:
wetterberg wrote:yeah I think the bcr IS controllable over midi, the lights on the buttons as well... so what you need is *more* lights, John?
I know that sounds crazy, but if I were to use some of the buttons for visual feedback (say scrolling lights or activity monitors) then they are no longer useful as buttons as buttons need visual feedback as well. Thats why I'm looking for alternatives.
so that's a yes, then?

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Wed Mar 24, 2010 2:37 am

Yes. I need the lights on the bcr to do what those lights normally do and I want a row of led's to simply scroll in tempo or possible be activity lights for drum beats.
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Wed Mar 24, 2010 8:31 am

Another option; an easy-peasy way:
http://www.eroktronix.com/
-it's 149 bucks, but you can probably wire it directly to the midi output of the BCR and thus keep it all internal

User avatar
Johnisfaster
Super Deluxe Wiggler
Posts: 4231
Joined: Fri Mar 13, 2009 2:08 am
Location: Town

Post by Johnisfaster » Wed Mar 24, 2010 4:11 pm

wetterberg wrote:Another option; an easy-peasy way:
http://www.eroktronix.com/
-it's 149 bucks, but you can probably wire it directly to the midi output of the BCR and thus keep it all internal
just a tad more $ than I'd prefer but I think that looks pretty good, I like the fact that I understand it right when I look at it ;)

good stuff andreas
JensenJohn.bandcamp.com

User avatar
wetterberg
Super Deluxe Wiggler
Posts: 7673
Joined: Thu Jul 24, 2008 5:31 pm
Location: Copenhagen, Denmark.

Post by wetterberg » Wed Mar 24, 2010 4:19 pm

good lord, I had completely forgotten this beauty:

http://www.division-6.com/products/midify.php

MIDIFY!
tiny, easy to work with and 12 outputs. It's also just 35 bucks! :)

Post Reply

Return to “Music Tech DIY”