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  • jschoolie 1:09 am on March 7, 2014 Permalink | Reply  

    Line 6 DL4 Smart Switch Mod in Beta Testing! 


    Hey Everyone!
    I’m to the point where I feel like I’m ready to sell this mod to a few brave beta testers! The kit will include all of the components required to do the mod (custom PCB, programmed microcontroller, footswitch, resistors, etc.). You’ll need to be able to solder and connect wires to the DL4 PCB, as well as assemble the Smart Switch PCB.

    Check out our shiny new website for more details.

    • Benjamin 8:53 am on August 7, 2014 Permalink | Reply

      I would like to get on the list to purchase the DL4 mod. I’m guessing your site got blown up from the number of people emailing to get on your list. Every time I try and fill out the email form to get on the waiting list I get this message when I click “Place Order”….

      Internal Server Error

      The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.

      I’m guessing, like so many others that saw you on Reverb’s “The 7 Best DL-4 Mods,” that your simple web page has been over run. Thought I’d try to contact you and let you know this way. Also to hopefully get on the list for the mod as well. Best of luck to you guys!

      • jschoolie 9:20 am on August 7, 2014 Permalink | Reply


        Thank you so much for letting us know! We are working on fixing it now. Email me at schoolcraft.rj@gmail.com with your full name and address and I’ll get you on the list. My apartment’s mail room lost my last batch of PCBs so there may be a delay before I can start sending out orders because I have to track those down first. Thanks again!

  • jschoolie 8:30 am on July 3, 2013 Permalink | Reply
    Tags: , DL4, Dotted Eighths, Line 6, Mod, Tap Tempo   

    Line 6 DL4 Dotted Eighth Tap Tempo Mod 

    Hey guys,

    So almost a year ago now, my brother Brian and I decided to make a dotted eighth tap tempo feature available on a Line 6 DL4 that I use on my guitar rig. We used an Arduino platform to prototype the project. I have been successfully using the mod for about 8 months now. Check out these videos for more info:

    Here’s the full source code for a standard Arduino or a standalone ATMega328 chip:

    I noticed there was a bug in the original code I posted. I went through and parsed a lot of stuff down in my original source code but I apparently made some errors. This code is the original source code and it is fully functional! 🙂
    (Read the rest of this post…)

    • Troy 9:57 pm on September 21, 2013 Permalink | Reply

      awesome mod. Do you have diy kits yet? If not would you be willing to hook me up with a schematic or possibly just some more details on this?

      • jschoolie 10:19 pm on September 26, 2013 Permalink | Reply

        Thanks! I’m working on finalizing everything right now. I’m very close to having a kit put together. I finished revising the pcb layout/schematic for the mod last night. The revised version uses an ATtiny85 and everything fits on a 1×1 pcb that fastens to the original screw holes on the DL4. Sorry for things moving so slowly, I’m currently enrolled in engineering at Purdue which eats up most of my free time 😉

        • Troy 10:46 pm on September 26, 2013 Permalink | Reply

          No prob. Thanks a lot for posting the code. I was missing the transistor part of the circuit and it gave me fits, but I was finally able to figure it out with an arduino uno and a transistor. I’m just a civil engineer (EIT)… It takes us a little longer to catch on. I think you would have a huge market if you started offering this mod. Thanks again for posting your code!

          • jschoolie 11:36 pm on September 26, 2013 Permalink | Reply

            You’re Welcome! I’m glad you got it working. Lol, you haven’t seen me try to build a bridge! And thanks, I hope so!

    • Troy 9:34 pm on September 30, 2013 Permalink | Reply

      After playing with it for a few days I think i have noticed a weakness in the code at least as it functions for me. On slow songs sometimes I will depress the tap on the beat and let it back up on the and of the beat to help me tap in time. I find that subdividing the rhythm helps me lock it in better (I have been accused of not having rhythm). I’m not sure why this is happening but I’m thinking the HOLD_DELAY 750 is timing out and resetting the tapstate variable. Is there any reason in the way you coded it that the HOLD_DELAY can’t equal 2002 to match the RESET_TIME? Was the selection of 750 arbitrary or did you have a reason?

      • jschoolie 12:26 am on October 1, 2013 Permalink | Reply

        Ah, you’re running into the double preset part of the mod. On the full mod, I have an extra MOSFET switch hooked up that receives either 5V or ground from the arduino. When hooked up properly to the DL4 it will act like an expression pedal. Holding the switch down for 750ms (which is what appears to be happening on the slow songs) flip flops the 5V/ground output from digital pin 8 I think, and it does reset the tap counts thus messing up the tempo. That feature should be pretty easy to remove in the debounce function as it is only necessary if you want the double preset thing to work. I’ll take a look at it tomorrow or Wednesday and try and post a version without that feature in it and that should fix it! Sorry about that!

        • Troy 12:07 pm on October 1, 2013 Permalink | Reply

          Thanks. I appreciate it. I use the double preset wheel instead of the switch. Thanks again for posting the code. It has made my dl4 infinitely more useable.

    • Marius 9:35 am on October 3, 2013 Permalink | Reply

      Hello jschoolie, I’m interested in your mod on DL4. Can you send me the list of parts i need and some info so I can make one for mine?

      • jschoolie 11:14 am on October 3, 2013 Permalink | Reply

        Hey Marius, I’m actually fairly close to having a PDF with the instructions and parts list etc. put together and I will post it on here when I have it done in a few days.

    • Bobby Meeks 12:59 am on October 5, 2013 Permalink | Reply

      This is great… Have you heard of anyone trying this on the HD300/400 that sadly has no .8th feature? I may be your first Guinea pig…

      • jschoolie 6:01 pm on October 5, 2013 Permalink | Reply

        Thanks Bobby, and I haven’t heard of any one doing that but I’d be willing to give it a shot! There may be some modifications to the code/process in general but I’m sure it could be done.

    • Ulises 12:45 pm on February 1, 2014 Permalink | Reply

      Hey man!! I play in a worship group and i love the dl4 except for the part that there is no 1/8!! You’re video inspired me!!! I am 17 and i just bout the Arduino mega!! I spent so much money so i can copy that code into a micro-controller but i would like to know if u have finished your pdf file showing what kind of switch i need and what parts (resistors, capacitors,regulators) i need and where to put them in the pref-board! Please man!! God Bless You!

      • jschoolie 4:02 pm on February 6, 2014 Permalink | Reply

        Hey dude! Glad to hear you like the mod and I’m also glad to hear you are using your talents to serve the Lord. I’ll have the PDF done and posted within a couple of weeks. I’m waiting on parts to get in and get my directions tested out before I post anything official. Thanks for your interest!

    • Ulises 9:02 pm on February 21, 2014 Permalink | Reply

      Thank you soo much man!!! Please let me know asap when you get everything done!! I dont need a kit i just need a pdf with all the intructions and i can get the stuff my self! You will help me use my dl4 in a better way!! God bless man!!

      • jschoolie 8:41 pm on March 5, 2014 Permalink | Reply

        Hey dude, I just got everything up and running on our shiny new site: http://www.schoolcraftspecialties.com/SmartSwitch. It’ll have everything you need to get you going. The sites pretty new (i.e. we just learned how to write html a few weeks ago) so we are still working out a few kinks. If you see anything horrendous, please let me know lol 😉

    • jschoolie 1:21 am on March 7, 2014 Permalink | Reply

      Hey Everyone!
      I’m to the point where I feel like I’m ready to sell this mod to a few brave beta testers! The kit will include all of the components required to do the mod (custom PCB, programmed microcontroller, footswitch, resistors, etc.). You’ll need to be able to solder and connect wires to the DL4 PCB, as well as assemble the Smart Switch PCB.

      Check out our shiny new website for more details:


    • Ulises 8:35 pm on March 22, 2014 Permalink | Reply

      Hey man! did u receive my email?

    • Austin 5:15 am on June 10, 2015 Permalink | Reply

      Very cool! I am very new to avr programming, but this project really caught my attention. How easy would it be to add to the code allowing you to choose between a few different tap multipliers that are controlled via spdt switch of some kind? like choosing between 1/4, dotted 1/8 and 1/8.

  • jschoolie 10:03 pm on January 8, 2013 Permalink | Reply
    Tags: Alesis, , , garageband, , io, iO2 Express, iPad, iPad io, iPad recording, iPad3 io   

    iPad 3 Compatible Alesis iO2 Express Mod 

    I was wanting to come up with a way to record my guitar among other things with my iPad without having to drop the $180.00 or so on an Alesis iO dock that honestly wasn’t as functional as what I wanted. Plus, I had heard a lot of reviews saying that the iO Dock didnt work with the iPad 3. So, I started scouring the Internet looking for a better solution. That’s when I stumbled upon the iO2 Express by Alesis. I was thrilled when I saw that this device was about $100.00 less than the iO Dock. The only thing stopping me from buying the device was the fact that I would have to modify it a bit to make it work with my iPad (the iO2 Express was intended to be used with CubaseLE on a PC or Mac). After buying it, I realized that I had a little more work to do than what I thought.
    To make the device work with my iPad I had to isolate the iO2’s power from the iPad because the iPad couldn’t provide enough current to power the device. So, I opened up the iO2 and removed the existing USB B female jack, making sure to remember which pin was where (i.e. power pin, ground, data+, data-). Next, I made a Franken-cable of sorts to provide +5V to the iO2. I cut the head off of one end of an instrument cable and I also cut the head off of one end of a USB cable leaving the USB A head that normally plugs into a computer. I stripped off the end of both cables to expose the inner wires. On the USB cable there were five wires: Red, black, white, green, and bare. The red wire is the +5V power line, the black is ground, white is data negative, green is data positive, and the bare wire is the chassis ground. The only wires I cared about were the red, black, and bare ones. On the instrument cable, there were two wires. One was the inner insulated wire which went to the tip of the plug and the other was the outer bare wire which went to the sleeve of the plug. I attached the red wire of the USB cable to the tip wire of the instrument cable. I also attached the black and bare wires of the USB cable to the sleeve wire of instrument cable. Finally, I wrapped each connection with electrical tape to ensure good insulation to prevent shorts. On to the iO2. On the PCB of the iO2 I installed a female instrument cable jack. I attached the tip connection to the +5v pin and the sleeve connection to ground (note how this corresponds with the Franken-cable’s setup). Next, I mutilated yet another USB cable again cutting off the head and leaving the A end intact. This time, I wanted the black, white, green, and bare wires. I attached the green wire to the data+ pin, the white to the data- pin and both the black and bare wires to ground. Finally I slapped some electrical tape on there to try and hold everything together and to provide insulation. You can see in one of the pictures where all the wires go. I just attached the bare wire to one of the old through hole mounts for the original female USB B jack.
    Beyond the mods to the actual iO2 I had to buy the Apple Camera Connection kit for about $20 on Ebay. I also had to buy a USB hub because for some reason the iO2 won’t work with the iPad without it. It seems almost as if the hub tricks the iPad. That’s the only part of this whole thing that I honestly have no idea why it works. I found that fix by googling some iPad forums. Anyway, when operating the device, use the Franken-cable to provide the iO2 with power. I just plug the USB end into my Apple charger because it outputs +5V (any other USB based charger should work) and I plug the instrument cable end into the jack I installed on the iO2. Plug the USB cable that has its data pins connected to the iO2 into the USB hub, plug the hub into the Camera Connection Kit, and plug the CCK into the iPad and it should work…hopefully.
    I’ve really gotten a lot of use out of this setup. I use it for recordings a bit, but much to my surprise, I use it quite a bit more as an interface with an oscilloscope app I found in the App Store. Believe it or not it works pretty well! We tested it against an actual analog oscope to find that the waveforms look the same and measure about the same as well! All in all, I put about $100 into the project which was totally worth it in my opinion.iO2 PCB with Female 1/4" Jack and new USB Cable

    Wiring on iO2 PCB

    Whole Setup (Minus iPad)

    Screenshot of My Oscope App

    • Raymo 10:52 am on October 16, 2013 Permalink | Reply

      Hey, did you try a self powered hub, I’m just wondering if this would have worked rather than having to do the power mod to the io2

    • len 5:13 pm on December 17, 2013 Permalink | Reply

      Cool mod 😀 hey I have one of these too – It won’t power on via an apple USB charger tho or HTC? I like to use with a HV30 camcorder on the go via beachtech XLR inputs. Power is the only issue – I guess I could carry a laptop with it all hooked up. Can this run stand alone from a USB charger tho? thx bro.

      • jschoolie 8:44 pm on December 18, 2013 Permalink | Reply

        Thanks! I believe it needs to have an actual USB data connection for it to power up, but that’s just a guess, not a fact.

    • len 4:10 am on December 19, 2013 Permalink | Reply

      Yes – Tried via a few chargers does not power on – lookd like windows XP driver once loaded nothing to download 🙂 then it powered on – old T23 with the lid closed – setup power and lid switch first in CPanel not to sleep – is used for car data logger so already set. 🙂 now mobile just bit heavier chunky T series – has better shielded usb ports compared to most netbooks – these are USB1 and still works. HV30 sees a good signal in via DXA-4 balanced TRS outs from iO2 to XLR. Another good find was the HV30 actually can use a SM7B x DXA-4 without the iO2 – works ok – and a little better with the i02 gain around 1/2 to 3/4. iO2 now provides phantom powering within the budget.”Hard wired LAV” setup . Cant fault this for price .

    • Mark 5:21 pm on December 28, 2013 Permalink | Reply

      Looks like a cool set up. I bought a m-audio m- track plus and when I used it with garage band I had some delay and bad quality because it was not working great with garage band. Have you experienced any problems with using the interface itself other than the power issue?

      • jschoolie 5:07 pm on December 31, 2013 Permalink | Reply

        Thanks! Nope, I haven’t experienced any trouble or delays with Garageband or any other app that uses the usb audio interface using this setup.

  • jschoolie 10:07 pm on September 17, 2012 Permalink | Reply
    Tags: , , iso box   

    Iso Box V.1 pre-completion 

    I built this to isolate my speaker cabinet so I can play in smaller venues by miking my amp inside the box and running that to the sound board. It still needs some work though, and I need to finish the outer walls before putting it to use.


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