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  • #31
    It’s been a while since I last posted, just letting you guys know about my progress.

    As for midifying the console, I decided to take advantage of Admin’s advice and I bought the Midi module from Harrison labs. Just ordered today, when it comes I will install it and let you guys know how it went. The Arduino side of things was fun, but trying to reverse engineer the Allen matrix keying was just too much. I’m going to chalk this one up to experience and enjoy playing the organ for a while.

    Other than that, all that remains is finishing the headphone port, and putting the new covers on the HC12’s. I’m also going to disassemble and reconfigure the top light again so the bottom metal panel doesn’t bulge - just bothers me too much! Once I’m done all these side projects I will post the results here. However, now to start work on my pump organ!

    Comment


    • myorgan
      myorgan commented
      Editing a comment
      Larason2,

      Thank you for providing the update on your organ. It's good to hear how you will be progressing forward, both on the Allen and on the pump organ. I look forward to that update as well!

      Michael

    • Larason2
      Larason2 commented
      Editing a comment
      Thanks Michael! I feel this group has been very helpful and supportive of my projects. Looking forward to starting work on the pump organ as well!

  • #32
    I think you'll be happy with the Harrison MIDI kit. I installed one a year or two ago on an Allen MOS and it worked perfectly, doing what it does, which is to provide key on/off data for all three organ divisions. And at a very low price. The work of getting the little wires tacked onto the proper spots on the KBA board was a bit tedious, but I did it, and didn't take terribly long. Surprised me, because my eyesight isn't what it used to be, and my hands are not as steady as they once were.

    One quirk about the Harrison board you should know about -- the outgoing MIDI stream includes a continuous, non-defeatable "all notes off" message that goes out on all three MIDI channels you have selected for your three divisions. It only stops when a key is actually down in a given division. So when I was trying to get my VPO software to recognize the three divisions, it failed because all three were simultaneously broadcasting that same message.

    The trick is to block down one key in each division (swell, great, and pedal) BEFORE you start the procedure to assign each keyboard to a division of the VPO. Then, after you right-click the keys on-screen, simply tap a key on the desired keyboard. Hauptwerk or Grand Orgue will instantly recognize the keyboard. The key you have blocked down will be ignored, because the program will have not yet identified the manuals as MIDI sources when you do the blocking.

    Once you get all three keyboards recognized, you can then unblock those keys of course. If you are using a MIDI monitor program, you will see that constant stream of "all notes off" messages. And if your MIDI interface going to the computer has an activity light, you will see it flashing constantly because that message never lets up unless you are playing all three keyboards at once.
    John
    ----------
    *** Please post your questions about technical service or repair matters ON THE FORUM. Do not send your questions to me or another member by private message. Information shared is for the benefit of the entire organ community, but other folks will not be helped by information we exchange in private messages!

    https://www.facebook.com/pages/Birds...97551893588434

    Comment


    • Larason2
      Larason2 commented
      Editing a comment
      Thanks for the heads up! That’s very useful, looking forward to having Midi on this machine!

  • #33
    Well, I finally received the Harrison Labs circuit board, but I realized once it arrived that my version of the keyboard array board doesn't have a wiring diagram! So, I wasn't able to install it. I emailed Harrison Labs to see if they could provide me with a wiring diagram for my version of the board (keyboard array 2), but after 5 days I haven't heard from them. I removed the keyboard array board to install the Harrison Labs kit, but when I realized I wouldn't be able to install it, I replaced it, and also put some Deoxit on the RCA cables coming out of the DAC board again, since channel 2 had started to get lower volume again. I was sad to see that once everything was put back together, Channel 1 had stopped working! On the plus side, however, channel 2 appeared to be back at the volume it was previously.

    This left me without a working organ, so I decided I would try to get the Arduino working again, even if only temporarily. I felt that since the Allen circuits seemed to be affecting the function of the Arduino, maybe just unplugging the keyboard array board would reduce the interference enough for the Arduino to work. So I unplugged it again, and tried the Arduino. However, I still found that pressing some notes would also trigger other notes (for instance, C#1 would also trigger G1). To rule out that the Allen circuits were interfering, I removed the Allen wires from the key contacts, and found everything worked perfectly! So I'm afraid I had to remove the Allen wires from both keyboards and the pedals, but the plan is to rewire them again someday (I just removed them close to where they were soldered and bent them back, so they should be easy to resolder). The top manuals worked perfectly, but the pedals, however, didn't work right initially. Even though they were programmed the same, I found I got a constant stream of notes on and off for every note on the pedalboard! I figured this must be because the pedalboard reed switches are NC (Normally Closed) switches, so I reversed the polarity of the data variables using my sketch, and reversed which trigger is note on and which is note off, and now the pedal works perfectly! So I have a functioning organ again (at least all three divisions for MIDI), however I am sad to lose the Allen sounds. Hopefully I will be able to get both up and running again sometime in the future. I plan to post my Arduino project on the Arduino Playground, and when I do, I will link to that post here.

    So for future directions, the hope is that either I will be able to use the Harrison labs board after all, or I will be able to use John Kinkennon's kit once it becomes available. If neither of these work out, then I may have to further modify it to work with the Arduino. While I'm waiting, I'm going to add midi to the pedals using a John Kinkennon style addition of a potentiometer with a custom bracket. I might also temporarily remove the wires to the stops and wire them to the Arduino, so that at least I can use them for stop selection. At least I have plenty to do while I wait!

    On another side note, I finished the top light so that the metal cover doesn't bulge out. To do that, I removed the aluminum LED holder from the light, clipped off the switch and wired the two leads that turn the light on together. I drilled two small holes in the aluminum holder, and fastened them to the metal bracket with screws. The light has the same quality, but now no bulging. I've posted a picture of the assembly before I put it back together (though I did have to flip the aluminum frame around to get the same quality of light)

    Comment


    • jbird604
      jbird604 commented
      Editing a comment
      Nice work on the lighting. Too bad the HL converter didn't work out. I've not tried it on a MOS-2 organ, so can't offer any advice on that. On the MOS-1 organ that I converted with HL, the wiring was pretty simple. They did provide pictures of a couple different versions of the KBA in that case, but I have seen other MOS-1 KBA boards that are quite different and possibly not usable with the HL converter. Keep posting about your progress.

  • #34
    Well, I just published the project on Arduino Hub! Here is the link:

    https://create.arduino.cc/projecthub...-organs-f3756c

    I'll also make a post on the appropriate forum section for Midi controllers and such.

    Comment


  • #35
    It's been a while since I last posted, so I thought I would update you all on my progress. I finally managed to get the expression pedals working with the Arduino!

    The design for the hardware is based on one by John Kinkennon. However, I made a few modifications based on what was available locally. For the plastic, I obtained some clear acrylic. The potentiometers are 10k linear ones I got from Mouser. To attach the potentiometers to the acrylic, I cut a small panel of acrylic roughly the size of the potentiometer, roughened up the surface of the potentiometer and the acrylic pieces with sandpaper, and attached the potentiometer to the small piece of acrylic, and the small piece of acrylic to the larger one using JB weld and a small clamp. The acrylic sheet is attached to the wooden base using two small #4 screws and a small furniture hinge (and the hinge attached to the acrylic sheet with #4 machine screws and bolts). I used an aluminum rod similar to the one used by John Kinkennon, though I think the exact part number is slightly different. To get it to work, I used JB weld to attach an eye bolt to one end, and the other end attached to an elbow bracket using a washer and a #8 machine screw. The elbow bracket is attached to one of the pre-existing holes on the Allen expression pedal, which were just big enough to accept a #6 machine screw. The hinge was accomplished with some washers and a lock nut on the #6 machine screw. The white plastic that keeps the rod in position is a portion of a PFTE block I purchased from Robot Shop. The action is very smooth and reliable. Very happy with the results!

    The expression pedal code for the Arduino is very simple, I will update the Arduino Hub page hopefully soon with the updated code and schematics. For wiring, I used some of the same 10 conductor AWM cable I used for most of the rest of the organ. I ran into some problems initially, because I soldered the Arduino's 5V to the appropriate pin of one potentiometer, then a short cable from that pin to the same pin on the other potentiometer. I found however, that when the first potentiometer was at 0, it would deactivate the other potentiometer! I wired the 5V pin using the same length of cable to both potentiometers, and no more problems. I had to do a few versions of the code, because I had to rewrite it so that it would only send messages when the pedal is moved (best for Hauptwerk, and its midi learn function). I've posted a photo of the assembly before I wired it. I had to remove the line level adapter board to accommodate the assembly, but I'm planning to put it back in in another position.

    Comment


    • #36
      I also had another question. I had to take the line level adapter board out, but i’m wondering if I can hook up the 4 speakers directly up to the M4 Amp, 2 speakers per channel? Since the speakers are in parallel, it should still be 8 ohms. I’m wondering if the line level adapter boosts the signal at all?

      Comment


      • #37
        The line level adaptor serves two functions:
        1. It ensures that the signal level is compatible with other audio devices (including perhaps the M4 amplifier. I don't know.)
        2. It provides a low impedance output suitable for driving long signal lines.
        If your amplifiers are located more than say 20 feet away (YMMV) from the console bypassing the line adaptor can affect operational stability as well as negatively impact the audio quality.

        I don't understand your question regarding the speakers. Two 8 ohm speakers in parallel results in an impedance of 4 ohms, not 8 ohms. I know the S100 amps were rated for 4 ohm output, and while I suspect that the M4 would be similar, I don't know that for sure.
        Last edited by Admin; 04-12-2021, 02:50 PM.
        -Admin

        Allen 965
        Zuma Group Midi Keyboard Encoder
        Zuma Group DM Midi Stop Controller
        Hauptwerk 4.2

        Comment


        • Larason2
          Larason2 commented
          Editing a comment
          Thanks Admin! That answered my question. You’re right about the two speakers in parallel, I miscalculated. I’ll try to find another spot to mount the adapter board.

      • #38
        Just wanted to update on my progress! I have spent some time refining the code, and updating the code for the potentiometer. I decided that I would try my hand at getting the combination action to work with the Arduino as John Kinkennon suggested. To do that, I am using a second Arduino and rewiring the stops and pistons to send Midi messages to the other one, to then send off to the computer. At first, I thought I could rewire the mega, and accomplish everything through just one Arduino. However, I ran into trouble, in that when I wired multiple sets of rows to the same pins, I got some unusual behaviour from the keyboards (whenever I played a G, and the D a fifth above, it would also play C#! Not the most pleasing combination!). I also had trouble in that I thought it would be easier to rewire the Mega using a screw terminal shield. I found however, that it was tricky to screw the terminals just right, so that they had a good contact with the fine wires, and I also found that the analog pin values jumped around a lot more (so I had to sacrifice sensitivity to the expression pedal). To make things easier, I finally ended up using jumpers and IDC sockets on the AWM cable to make everything easier to rewire! It's not as permanent as soldering, but it works quite well for now.

        The plan then is to matrix the stop contacts and pistons, then use a second Arduino to read them and convert them into Midi signals. Then, I also plan to connect four MS23017 devices to provide current to the stop assemblies to enable the combination action to work. I'm thinking of using an Arduino Uno I have lying around, and since an Arduino Uno doesn't have as many pins as the Mega, I'm also toying with the idea of using a 3-8 line decoder or two for some or all of the columns. Still working on wiring the stop switches to a matrix for now then. The good thing is the organ is working once again, so I can go back to practicing!

        Comment


        • #39
          Another small update! I finally finished re-doing the front covers of my HC12's. I ended up getting some perforated steel sheet metal cut to the right size, which was pretty economical. Initially, I bought some plastic connectors from Parts Express, but the metal and the wooden cover were too heavy for them, and I broke two of them just seeing if the fit was right! So I ended up buying some L brackets from Home Depot, and screwing them into place on the front of the cabinets, then at the sides of the frames. The perforated steel sheets were attached to the frames with a few #4 screws, which fit into the holes perfectly. The only problem is that I suspect the metal will vibrate when I operate the speakers. However, I have ordered some gasket leather from Steve's, so I plan to put a small amount of that on either side of the screws to prevent vibration. Otherwise they look quite good!

          Thinking about it some more, instead of using the Arduino Uno, I plan to use two more MS23017 units to run the rows and columns of the stops and pistons. It will be slower than the Arduino pins, but I suspect it will still be fast enough, and I will still get away with only using one Arduino, the Mega. Next step is to finish wiring the stop and piston matrices.

          Comment


          • AllenAnalog
            AllenAnalog commented
            Editing a comment
            While good to keep cats and small children from damaging the cones of your speakers, I have some concern about the change in frequency response of your speakers with the small diameter perforations and percentage of transparency in that metal. I'll be interested to know what, if any, differences you hear with and without those covers.

          • myorgan
            myorgan commented
            Editing a comment
            Larason,

            I'm assuming you already know Allen attached their speaker grilles with velcro stapled to the speaker & grille frame? The velcro helps mitigate any rattles you may encounter.

            In my case, I just ordered acoustically transparent grille cloth (see Larry's concern above), stretched it over the back of the grille, and stapled it there with a staple gun. They've lasted well so far, and there are no issues with unwanted rattles.

            Michael

          • Larason2
            Larason2 commented
            Editing a comment
            Yes, when I received the speakers, they had the wooden frames with speaker cloth attached, and they were attached to the cabinets with velcro. Unfortunately, one of the frames broke, damaging the speaker cloth, and the velcro pulled off with the frames on nearly every other speaker. So, I had to replace it one way or another, and the velcro didn’t seem to be very well affixed to the cabinet. In retrospect, I probably would have saved a lot of trouble getting new speaker cloth and finding a better way to affix the velcro, but it’s too late for that! When I purchased the metal, I looked online to see whether it would work or not, and while I found a lot of conflicting opinions, overall it seemed as though it should probably be ok. Well, I’ll test them and see how they sound! I think they look attractive, and I think it’s unlikely that 4 HC12’s will not have enough Bass! I’ll report back when I’ve tested them!

        • #40
          Time for another update! I haven't been able to test the speakers yet with the new metal grilles, but I will report back once I have (they are all hooked up, just need to try them!). Instead what I have been working on is trying to get the pistons and stops switches working! The keys, pedals, and expression pedals all work, and I finally managed to get the pistons working. I wired the pistons in a 6x6 matrix, at first with the MCP23017's, but I couldn't figure out how to get the 23017's working. I also found that including the MCP code slowed down the key sensing quite a lot (even if I instructed the program to run the main loop 3 times, then the MCP loop). In retrospect, I think I was trying to power the MCP23017's off of the 5v pin that is dead on my arduino mega, so I will still try to get them working again!

          Instead what I ended up doing is wiring all the stops and pistons to my Arduino Mega, as well as to an Arduino Uno that I had lying around. I found some very useful code that allowed the Arduino Mega to act as a MIDI Thru from the Uno, only needing to connect two wires (the ground, and the Tx from the Uno to the Rx on the Mega). At first I had troubles with the pistons, with some pistons triggering two notes, but then I discovered that I had accidentally driven a screw into one of the ribbon cables, and shorted two rows! Once I cleaned that up, the problems disappeared. My remaining trouble though, is that when I trigger one stop, it triggers all of the stops at the same time! I discovered this is because the top leaf of the switch is actually electrically coupled to each stop mechanism, which are all electrically coupled as well through the metal stop board rail. To solve this problem, I have ordered some red insulating varnish, which I plan to use to coat the switch leaf except for the contact. If that doesn't work, my plan is to varnish just the ends, and to adhere some conductive metal onto the ends that touch the other switch leaves.

          I'm hoping to try the MCP23017's again, but this time powered through the Arduino Uno, where I feel I can trust the 5v pin a bit more. However, the plan is to connect the wires to the combination action power supply, as well as to the green wires triggering each switch. I'm also waiting on one of John Kinkennon's boards. I'm hoping it will let me wire up everything more easily, especially since everything already appears to be wired to take advantage of it! That will also help free up the two arduino's for future projects. My gratitude to him for his generosity!

          I'm still not giving up on the original organ system, though with each new modification it will be harder to get it working again as it was! I'm also toying with the idea of taking the boards out and mounting them in an enclosure, and turning it into a midi module using one or more Arduino's. That will probably be a lot of work, however!

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