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Adding midi to an organ pedalboard

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I have an organ pedalboard that I want to hook up to my digital keyboard and/or computer with midi. I've been googling around the net for a few days and just now found this site. I know I need a midi encoder that can handle 32 notes, and I need 32 magnetic reed switches and magnets. That's where I'm at now, so any help is appreciated. I can follow instructions very well, so things like "go to this site" "buy this item" etc., work well for me.

Thanks!

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welcome!

I'm thinking what you need is a Core kit, a DIN kit, and LCD, ribbon cable, connectors, etc.  If you're in the US, SmashTV has almost everything you need here http://www.avishowtech.com/mbhp/buy.html.  I can't remember the other one, but the wiki will hopefully be up and running again soon.

The Core is the brains of the project and each Digital IN board has 32 inputs so you'll only need one.

You'll also need basic soldering supplies and some practice if you never soldered before.

That should be a good start for you.  I'm sure there are a few things I am forgetting though.

-Trevor

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Yes, I'm in the US, in Texas.

Ok, great. I see the Core Kit, that's item number 06. I see the LCP, number 49, but it's sold out. Is there an alternative I can use or can it be left out? There are 32 pedals, I'm not sure how the wiring works. Would two 16-pin ribbon cables do it, or do I need 4? And I see the ribbon cable connectors just above them.

I've only soldered with one of those little strips of metal Radio Shack sells that you melt with a match, but I'm sure I can figure it out. How do I do the actual connection to the pedals? In my reading I saw that magnetically actuated reed switches are the most reliable option. What do you think? Do you know where to get those and magnets? However I do it, there are two leads to the switch, so 32 x 2 = 64 connections at the pedals. That's why I'm thinking I'll need 4 16-pin ribbon cables. How do you know which wire from the ribbon goes to which pedal?

Here's another question. I read somewhere that there are two ways to wire pedals for midi: one-to-one connections or using an 8 x 4 scan matrix. One-to-one is pretty straight forward, but I have a question about the scan matrix configuration. It's my understanding that there are 8 columns and 4 rows. So if I push the first note, it will be (1,1). The second note will be (1,2) and so on until you get to the ninth note and it will be (2,1). How does it handle polyphony? Let's say I'm pushing the first note (1,1) and the tenth note (2,2) at the same time. How can it distinguish that from the second note (1,2) and the ninth note (2,1) at the same time? Both would signal the first and second row and first and second column. Which type of wiring configuration does the Core kit use?

Sorry for all of the questions, but I'm brand new to this and looking forward to do starting the project. I appreciate your response.

Thanks!

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Yes, I'm in the US, in Texas.

Ok, great. I see the Core Kit, that's item number 06. I see the LCP, number 49, but it's sold out. Is there an alternative I can use or can it be left out? There are 32 pedals, I'm not sure how the wiring works. Would two 16-pin ribbon cables do it, or do I need 4? And I see the ribbon cable connectors just above them.

You can find the LCDs on ebay very cheaply.  Look at the midibox site to make sure you get the right type.  Two 16 way ribbon cables will do the job if it is a 32 note pedal board.

I've only soldered with one of those little strips of metal Radio Shack sells that you melt with a match, but I'm sure I can figure it out. How do I do the actual connection to the pedals? In my reading I saw that magnetically actuated reed switches are the most reliable option. What do you think? Do you know where to get those and magnets? However I do it, there are two leads to the switch, so 32 x 2 = 64 connections at the pedals. That's why I'm thinking I'll need 4 16-pin ribbon cables. How do you know which wire from the ribbon goes to which pedal?

Does your pedal board have a switches built in, can't these be reused?  Otherwise reed switches are a good choice, although you may need to experiment to get the right "feel" from the pedal board.  Many church organs (at least in the UK) use Kimber-Allen switches (do a search on google to find their site).

Here's another question. I read somewhere that there are two ways to wire pedals for midi: one-to-one connections or using an 8 x 4 scan matrix. One-to-one is pretty straight forward, but I have a question about the scan matrix configuration. It's my understanding that there are 8 columns and 4 rows. So if I push the first note, it will be (1,1). The second note will be (1,2) and so on until you get to the ninth note and it will be (2,1). How does it handle polyphony? Let's say I'm pushing the first note (1,1) and the tenth note (2,2) at the same time. How can it distinguish that from the second note (1,2) and the ninth note (2,1) at the same time? Both would signal the first and second row and first and second column. Which type of wiring configuration does the Core kit use?

Scan matrix are useful when there are lots of inputs, but in your case I would wire the pedal board using the "standard" arrangement since you have so few inputs (you only require a single DIN), and because that is best tested and documented. The standard arrangement involves a single/shared ground connection to all the switches and for each switch an individual connection back to the DIN which creates a circuit when the switch is closed and breaks the circuit when the switch is open.

Hope that helps,

James

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I see the LCP, number 49, but it's sold out. Is there an alternative I can use or can it be left out?

Make the effort to find an LCD panel. It is a great help for your first MIDIbox.

There are 32 pedals, I'm not sure how the wiring works. Would two 16-pin ribbon cables do it, or do I need 4? And I see the ribbon cable connectors just above them.

You need 4 10-pin ribbon cables for SmashTVs DIN board. 8 wires in each cable are used for inputs and the other two have the common connection.

How do I do the actual connection to the pedals? In my reading I saw that magnetically actuated reed switches are the most reliable option. What do you think? Do you know where to get those and magnets?

You can get reed switches from Mouser. I'll dig up a specific part number and post it later. You can get a pack of 50 magnets at Michaels. I'd suggest working out your switches before you even bother to order the MIDIbox kits. It is likely to be the most time consuming part because you have to work out the mechanical aspect of supporting things. A pedalboard needs to be sturdy. It will take a lot of abuse.

However I do it, there are two leads to the switch, so 32 x 2 = 64 connections at the pedals. That's why I'm thinking I'll need 4 16-pin ribbon cables. How do you know which wire from the ribbon goes to which pedal?

One side of all the switches will we wired together and connected to the common connection. The other sides of the switches will be the 32 inputs. So you have 33 connections to make. There will be 8 wires available for that 33rd common connection.

Which type of wiring configuration does the Core kit use?

The Core kit doesn't "use" any particular type of wiring configuration in the sense you are asking. It is the "brains" of a MIDIbox and it normally only connects to other MIDIbox boards like the DIN. The type of wiring configuration used depends on the "project" (software program) you load into the MIDIbox. You'll want the MIDIIO128 project which uses 1 to 1 inputs.

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Wow, I can't believe the responses I see here. I've posted on other forums and rarely get a useful reply. Thanks so much!

I did an ebay search for an LCD here. It's 20x2, like the one on SmatshTV that was sold out. What do you think?

The pedals currently have no switches at all, which is why I wanted to add the reed switches. My idea to is connect a magnet to the end of each pedal. On a piece of wood which will be mounted at the end of the pedalboard, I'll connect the reed switches. This way all of the electronics will be on that board, so if I ever need to take it off, just a few screws will disconnect it from the pedalboard. The only thing left with the pedalboard would be the magnets.

I went to the Mouser site to look for reed switches. They have way to many options for me to know which one to get. Can you be more specific? There's a Michael's locally, I'll stop there for the magnets. Any suggestions on the size/strength of the magnets?

I'm a little confused on the ribbon cables. How do these connect to the DIN board? How does the board know which cable is connected to which note? The 8 wires for the common ground...are these connected to each other, or are they connected internally on the board? Other than the 32 note and one ground connection, what else do I need to anticipate? Is it hard to connect the LCD?

Is there a power connection needed, or is it powered through the midi cable?

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I did an ebay search for an LCD here. It's 20x2, like the one on SmatshTV that was sold out. What do you think?

Too expensive. Try this:

2x16 LCD

The pedals currently have no switches at all, which is why I wanted to add the reed switches. My idea to is connect a magnet to the end of each pedal. On a piece of wood which will be mounted at the end of the pedalboard, I'll connect the reed switches. This way all of the electronics will be on that board, so if I ever need to take it off, just a few screws will disconnect it from the pedalboard. The only thing left with the pedalboard would be the magnets.

That will work but you have to do some fiddling to figure out the orientation and location of the reeds.

I went to the Mouser site to look for reed switches. They have way to many options for me to know which one to get. Can you be more specific? There's a Michael's locally, I'll stop there for the magnets. Any suggestions on the size/strength of the magnets?

Mouser 816-RI-01BAA should work. As should the ProMAG 3/4" round button magnets.

I'm a little confused on the ribbon cables. How do these connect to the DIN board? How does the board know which cable is connected to which note? The 8 wires for the common ground...are these connected to each other, or are they connected internally on the board? Other than the 32 note and one ground connection, what else do I need to anticipate?

The newest DIN boards from SmashTV use a 10 pin IDC connector for the inputs. There is a configuration table you'll use to define what each input does. You can connect any or all of the 8 common wires to the switches. Anticipate asking a lot more questions.  ;D But seriously, you just have to dive in and start doing this. You can't ask and anticipate everything before you start.

Is it hard to connect the LCD?

No harder than a pedalboard.  ;D  I wrote a PDF guide on how to do it. 

Is there a power connection needed, or is it powered through the midi cable?

You need a "wall wart" for power. You probably have something that will work if you save them from all the electronics junk that you throw out.

Since you seem like a meticulous sort, take notes and pictures of the project as you go and write a guide on how to do this sort of thing when you are done. More and more people want to create MIDIfied pedalboards.

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Too expensive. Try this: 2x16 LCD

Well, the one here was 20x2. If 16x2 works, that's fine with me. Thanks for the link.

Mouser 816-RI-01BAA should work. As should the ProMAG 3/4" round button magnets.

I was actually think about 1/2" or 3/8" for the magnets because I don't want them to actuate the switches of adjacent pedals. Have you had good luck with 1/2"?

You can't ask and anticipate everything before you start.

I know, but I can try to put together a fairly good parts list.

I wrote a PDF guide on how to do it. 

That's cool, thanks.

You need a "wall wart" for power. You probably have something that will work if you save them from all the electronics junk that you throw out.

Any particular voltage? Do I need to solder a connection onto the board for it?

Since you seem like a meticulous sort, take notes and pictures of the project as you go and write a guide on how to do this sort of thing when you are done. More and more people want to create MIDIfied pedalboards.

That's a possibility. I still think the hardest step is collecting all the necessary parts...I may have a different opinion after I'm finished :O)

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Any particular voltage? Do I need to solder a connection onto the board for it?

That's a possibility. I still think the hardest step is collecting all the necessary parts...I may have a different opinion after I'm finished :O)

I'd suggest a 9V that can handle at least 500mA.  That seems to be the general consensus when using an LCD.  I have a 9V 500mA and a 9V 850mA and they both work just fine.  The voltage regulator will probably get hot if you go any higher than 9V.

If you order the Core kit, it comes with a crimp connector and pins that are soldered to J1.

Here are two pictures of what I have done so far.  I am using DOUTs, but they will be wired similarly to what you are doing.

n210901242_30516878_8711.jpg

n210901242_30516879_8996.jpg

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I was actually think about 1/2" or 3/8" for the magnets because I don't want them to actuate the switches of adjacent pedals. Have you had good luck with 1/2"?

I'm just at the point of trying to figure out how I am going to support the reed switches. So far all I've done is to experiment with possible positions and orientations. I can say the positioning is not intuitive. My magnets are attached to L brackets that were originally used to close mechanical switches in the console. (This is a pedalboard from a Conn 652.) They have their flat surface parallel to the floor. The best position for the reeds seems to be off to one side of the magnet, with  perhaps a 1/4" gap. Remember that the magnetic field is something like a doughnut with the magnet in the hole. The field is strongest somewhere beyond the magnet.

The concern about activating adjacent switches is legitimate. As best I can tell, it doesn't look like it will be a problem using the 3/4" magnets. The other concern is to have the switch activate at about the halfway point on pedal travel and then not drop out as the pedal bottoms out. That seems a bit trickier as far as finding the best setup. Since 50 of these magnets are about $7, it is no disaster if you change your mind about the size.

One suggestion I received is to attach the reed switches using beeswax so they can be repositioned if necessary.

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Ok, I'm ready to start ordering parts. Please feel free to comment on my parts list:

From http://www.avishowtech.com/mbhp/buy.html:

#02 Core kit with PIC18F452

#04 DIN Kit

#33 10 pin Female ICD Connector x 4

#34 10 pin Ribbon Cable x 4

From http://character-lcd-lcds.shopeio.com/inventory/details.asp?id=1197&cat=Lcds&sub=Character%20Lcd

The Data Vision DV-16236-S1FTLY LCD

From www.mouser.com

816-RI-01BAA Switches x >=32

From any craft store:

Magnets  x >=32

From misc unused electronic device:

Power supply

I'm going to experiment with the magnets/switch position to try to get a precise actuation point and then mount the switches on a wooden board which I mount to the end of the pedalboard.

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I'd also order #33 x2 so you can connect your LCD and #24 so you can put a header on your LCD.  Don't forget to check the LCD datasheet though to make sure the pins will match up.

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I'd also order #33 x2 so you can connect your LCD and #24 so you can put a header on your LCD.  Don't forget to check the LCD datasheet though to make sure the pins will match up.

I thought you had to solder the wires to the LCD. So, one ICD connector for each end of the LCD's ribbon cable?What's an LCD header?

What about the midi jack(s)? Do I need and in and an out or just the out? Will #20 or 21 be what I need?

Thanks,

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Sorry to jump in this thread, but I too am looking to add midi to a organ pedal board. I understand the basics outlined above. But using the CORE plus the DIN does that just give me note on and off information especially as I would prefer to keep the switches in the board than replace. Is that OK?

Also the board has a pedal too does this mean I have to add a analogue input board too?

Also I'm really knew to this to upload to the pic can I just use a basic pic development kit say from Rapid or similar?

Does the core module have the Midi out built in or do I need a further board?

Cheers for the amazing info so far

Aus

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Also the board has a pedal too does this mean I have to add a analogue input board too?

You can add up to 8 analog inputs directly to the Core. If you use the MIDIIO128 project, and you should to handle the DIN board inputs from the pedal switches, you need a minor modification to that code to process the analog input. The topic was discussed on the Miditzer virtual organ forum and modified code was posted. You'll need to register on that forum to see this topic area:

http://www.jbwebserver.net/mforum/forum_posts.asp?TID=1139

I think there are posting here that discuss it but maybe not quite so reduced to a cookbook approach.

Also I'm really knew to this to upload to the pic can I just use a basic pic development kit say from Rapid or similar?

There are suppliers of low cost PCBs and kits for building MidiBoxes. Look in the Wiki.

Does the core module have the Midi out built in or do I need a further board?

MIDI In and Out are provided by the Core module.

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I thought you had to solder the wires to the LCD. So, one ICD connector for each end of the LCD's ribbon cable? What's an LCD header?

What about the midi jack(s)? Do I need and in and an out or just the out? Will #20 or 21 be what I need?

Most LCD's have a single row of 16 for the connection, so they need to be soldered.  Your LCD has two rows of 8 which is what the IDC connector is. So yes, one IDC on each end of the ribbon cable.  Just don't forget to check the datasheet to make sure the pins match up.  The pin headers are soldered to the boards and are what the IDC connectors plug into.  You can buy a #24 or you can use leftovers from your CORE kit if you decide not to solder all the headers.

The CORE comes with the midi jacks. You'll need to solder both.

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Most LCD's have a single row of 16 for the connection, so they need to be soldered.  Your LCD has two rows of 8 which is what the IDC connector is. So yes, one IDC on each end of the ribbon cable.  Just don't forget to check the datasheet to make sure the pins match up.  The pin headers are soldered to the boards and are what the IDC connectors plug into.  You can buy a #24 or you can use leftovers from your CORE kit if you decide not to solder all the headers.

The CORE comes with the midi jacks. You'll need to solder both.

So I solder the DIL header to the LCD, and use the IDC to snap on the ribbon cable and plug into the DIL header? Does the CORE also accept an IDC on a DIL header? Do I need to solder the headers or just plug them in?

Also, my LCD and two rows of 7 on one end and the two power connections on the other.

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Hi, SB,

Here's a file saved in my rather ambitious research resources that gives some ideas.

Don't know how practical or current they may be for your needs, but worth a glance:

http://www.westnet.com/~levins/organ/practice.html

PK

That's cool. That's for the link. I like the bench, it look's great. That's probably going to be my next project unless I come across something in the mean time.

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So I solder the DIL header to the LCD, and use the IDC to snap on the ribbon cable and plug into the DIL header? Does the CORE also accept an IDC on a DIL header? Do I need to solder the headers or just plug them in?

Also, my LCD and two rows of 7 on one end and the two power connections on the other.

Start from the CORE, it is the more standardized part of a MidiBox. You will solder a DIL header to the CORE PCB. A 2x8 IDC connector on a ribbon cable plugs into that. That puts the 16 LCD signals on specific wires within the ribbon cable. (Do you have my PDF guide to cabling an LCD?) Now you have to look at where those signals go on your LCD. It is unlikely that they go in the same places as they would be in another IDC connector but maybe you'll be lucky. One can change the order of the wires to some extent in an IDC connector but it is tricky and not terribly reliable. I wouldn't suggest it if you don't have experience dealing with IDC connectors. Most likely you'll have to solder the wires of the ribbon cable to the LCD.

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I've obtained two 61-note keyboards that I'd like to use for the manuals. I'd like to mount them together so that the height and depth differences match those of a normal 2-manual organ. Does anyone know the proper measurements?

Also, I'm going to have to crack at least one of the cases to allow them to be as close as is required. Other than harvesting material from a rubbermaid tub, are there good alternatives to make a new "double" case?

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Manuals are 2.5 inches from key top to key top. They can also be slightly angled so the upper manual rises toward the rear. I don't have the amount of this close at hand. It's slight but it makes the keyboards more comfortable to play and it might help with clearances. If you want to slope the upper board I can track down the spec.

I plan a similar project and I am thinking in terms of a wood case based on my tools and skills.

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Manuals are 2.5 inches from key top to key top.

What about depth? (how much closer is the bottom manual than the top?)

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Standard measurements for a pipe organ console can be found in a drawing on the American Guild of Organists (AGO) website.

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Standard measurements for a pipe organ console can be found in a drawing on the American Guild of Organists (AGO) website.

Can you post a link to the drawing?

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